RTEMS Shell Guide (6.a3cfaea).¶

2.2.1. Customizing the Command Set¶

The user can configure specific command sets by either building up the set from individual commands or starting with a complete set and disabling individual commands. Each command has two configuration macros associated with it.

CONFIGURE_SHELL_COMMAND_XXX

Each command has a constant of this form which is defined when building a command set by individually enabling specific commands.

CONFIGURE_SHELL_NO_COMMAND_XXX

In contrast, each command has a similar command which is defined when the application is configuring a command set by disabling specific commands in the set.

2.2.2. Adding Custom Commands¶

One of the design goals of the RTEMS Shell was to make it easy for a user to add custom commands specific to their application. We believe this design goal was accomplished. In order to add a custom command, the user is required to do the following:

• Provide a main-style function which implements the command. If that command function uses a getopt related function to parse arguments, it MUST use the reentrant form.

• Provide a command definition structure of type rtems_shell_cmd_t.

• Configure that command using the CONFIGURE_SHELL_USER_COMMANDS macro.

Custom aliases are configured similarly but the user only provides an alias definition structure of type rtems_shell_alias_t and configures the alias via the CONFIGURE_SHELL_USER_ALIASES macro.

In the following example, we have implemented a custom command named usercmd which simply prints the arguments it was passed. We have also provided an alias for usercmd named userecho.

#include <rtems/shell.h>
int main_usercmd(int argc, char **argv)
{
    int i;
    printf( "UserCommand: argc=%d\n", argc );
    for (i=0 ; i<argc ; i++ )
        printf( "argv[%d]= %s\n", i, argv[i] );
    return 0;
}
rtems_shell_cmd_t Shell_USERCMD_Command = {
    "usercmd",                                                   /* name */
    "usercmd n1 [n2 [n3...]]",                                   /* usage */
    "user",                                                      /* topic */
    main_usercmd,                                                /* command */
    NULL,                                                        /* alias */
    NULL,                                                        /* next */
    S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH,   /* mode */
    0,                                                           /* uid */
    0                                                            /* gid */
};
rtems_shell_alias_t Shell_USERECHO_Alias = {
    "usercmd",                   /* command */
    "userecho"                   /* alias */
};
#define CONFIGURE_SHELL_USER_COMMANDS &Shell_USERCMD_Command
#define CONFIGURE_SHELL_USER_ALIASES &Shell_USERECHO_Alias
#define CONFIGURE_SHELL_COMMANDS_INIT
#define CONFIGURE_SHELL_COMMANDS_ALL
#define CONFIGURE_SHELL_MOUNT_MSDOS
#include <rtems/shellconfig.h>

Notice in the above example, that the user wrote the main for their command (e.g. main_usercmd) which looks much like any other main(). They then defined a rtems_shell_cmd_t structure named Shell_USERCMD_Command which describes that command. This command definition structure is registered into the static command set by defining CONFIGURE_SHELL_USER_COMMANDS to &Shell_USERCMD_Command.

Similarly, to add the userecho alias, the user provides the alias definition structure named Shell_USERECHO_Alias and defines CONFIGURE_SHELL_USER_ALIASES to configure the alias.

The user can configure any number of commands and aliases in this manner.

2.3.1. Attached to a Serial Port¶

Starting the shell attached to the console or a serial port is very simple. The user invokes rtems_shell_init with parameters to indicate the characteristics of the task that will be executing the shell including name, stack size, and priority. The user also specifies the device that the shell is to be attached to.

This example is taken from the fileio sample test. This shell portion of this test can be run on any target which provides a console with input and output capabilities. It does not include any commands which cannot be supported on all BSPs. The source code for this test is in testsuites/samples/fileio with the shell configuration in the init.c file.

#include <rtems/shell.h>
void start_shell(void)
{
    printf(" =========================\n");
    printf(" starting shell\n");
    printf(" =========================\n");
    rtems_shell_init(
        "SHLL",                       /* task name */
        RTEMS_MINIMUM_STACK_SIZE * 4, /* task stack size */
        100,                          /* task priority */
        "/dev/console",               /* device name */
        false,                        /* run forever */
        true,                         /* wait for shell to terminate */
        rtems_shell_login_check       /* login check function,
        use NULL to disable a login check */
    );
}

In the above example, the call to rtems_shell_init spawns a task to run the RTEMS Shell attached to /dev/console and executing at priority 100. The caller suspends itself and lets the shell take over the console device. When the shell is exited by the user, then control returns to the caller.

2.3.2. Attached to a Socket¶

TBD

2.4.1. Login Checks¶

Login checks are optional for the RTEMS shell and can be configured via a login check handler passed to rtems_shell_init(). One login check handler is rtems_shell_login_check().

2.4.2. Configuration Files¶

The following files are used by the login check handler rtems_shell_login_check() to validate a passphrase for a user and to set up the user environment for the shell command execution.

/etc/passwd

The format for each line is

user_name:password:UID:GID:GECOS:directory:shell

with colon separated fields. For more information refer to the Linux PASSWD(5) man page. Use a password of * to disable the login of the user. An empty password allows login without a password for this user. In contrast to standard UNIX systems, this file is only readable and writeable for the user with an UID of zero by default. The directory is used to perform a filesystem change root operation in rtems_shell_login_check() in contrast to a normal usage as the HOME directory of the user. The default content is:

root::0:0::::

so there is no password required for the root user.

/etc/group

The format for each line is:

group_name:password:GID:user_list

with colon separated fields. The user_list is comma separated. For more information refer to the Linux GROUP(5) man page. In contrast to standard UNIX systems, this file is only readable and writeable for the user with an UID of zero by default. The default content is

root::0:

2.4.3. Command Visibility and Execution Permission¶

Each command has:

• an owner,

• a group, and

• a read permission flag for the owner, the group and all other users, and

• an execution permission flag for the owner, the group and all other users.

The read and write permission flags are stored in the command mode. The read permission flags determine the visibility of the command for the current user. The execution permission flags determine the ability to execute a command for the current user. These command properties can be displayed and changed with the:

• cmdls,

• cmdchown, and

• cmdchmod

commands. The access is determined by the effective UID, the effective GID and the supplementary group IDs of the current user and follows the standard filesystem access procedure.

2.4.4. Add CRYPT(3) Formats¶

By default the crypt_r() function used by rtems_shell_login_check() supports only plain text passphrases. Use crypt_add_format() to add more formats. The following formats are available out of the box:

• crypt_md5_format,

• crypt_sha256_format, and

• crypt_sha512_format.

An example follows:

#include <crypt.h>
void add_formats( void )
{
    crypt_add_format( &crypt_md5_format );
    crypt_add_format( &crypt_sha512_format );
}

2.5.1. rtems_shell_init - Initialize the shell¶

CALLING SEQUENCE:

rtems_status_code rtems_shell_init(
    const char          *task_name,
    size_t               task_stacksize,
    rtems_task_priority  task_priority,
    const char          *devname,
    bool                 forever,
    bool                 wait,
    rtems_login_check    login_check
);

DIRECTIVE STATUS CODES:

RTEMS_SUCCESSFUL - Shell task spawned successfully others - to indicate a failure condition

DESCRIPTION:

This service creates a task with the specified characteristics to run the RTEMS Shell attached to the specified devname.

NOTES:

This method invokes the rtems_task_create and rtems_task_start directives and as such may return any status code that those directives may return.

There is one POSIX key necessary for all shell instances together and one POSIX key value pair per instance. You should make sure that your RTEMS configuration accounts for these resources.

2.5.2. rtems_shell_login_check - Default login check handler¶

CALLING SEQUENCE:

bool rtems_shell_login_check(
  const char *user,
  const char *passphrase
);

DIRECTIVE STATUS CODES:

true - login is allowed, and false - otherwise.

DESCRIPTION:

This function checks if the specified passphrase is valid for the specified user.

NOTES:

As a side-effect if the specified passphrase is valid for the specified user, this function:

• performs a filesystem change root operation to the directory of the specified user if the directory path is non-empty,

• changes the owner of the current shell device to the UID of the specified user,

• sets the real and effective UID of the current user environment to the UID of the specified user,

• sets the real and effective GID of the current user environment to the GID of the specified user, and

• sets the supplementary group IDs of the current user environment to the supplementary group IDs of the specified user.

In case the filesystem change root operation fails, then the environment setup is aborted and false is returned.

3.2.1. help - Print command help¶

SYNOPSYS:

help misc

DESCRIPTION:

This command prints the command help. Help without arguments prints a list of topics and help with a topic prints the help for that topic.

EXIT STATUS:

This command returns 0.

NOTES:

The help print will break the output up based on the environment variable SHELL_LINES. If this environment variable is not set the default is 16 lines. If set the number of lines is set to that the value. If the shell lines is set 0 there will be no break.

EXAMPLES:

The following is an example of how to use alias:

SHLL [/] $ help
help: ('r' repeat last cmd - 'e' edit last cmd)
TOPIC? The topics are
mem, misc, files, help, rtems, network, monitor
SHLL [/] $ help misc
help: list for the topic 'misc'
alias        - alias old new
time         - time command [arguments...]
joel         - joel [args] SCRIPT
date         - date [YYYY-MM-DD HH:MM:SS]
echo         - echo [args]
sleep        - sleep seconds [nanoseconds]
id           - show uid, gid, euid, and egid
tty          - show ttyname
whoami       - show current user
logoff       - logoff from the system
setenv       - setenv [var] [string]
getenv       - getenv [var]
unsetenv     - unsetenv [var]
umask        - umask [new_umask]
Press any key to continue...
rtc          - real time clock read and set
SHLL [/] $ setenv SHELL_ENV 0
SHLL [/] $ help misc
help: list for the topic 'misc'
alias        - alias old new
time         - time command [arguments...]
joel         - joel [args] SCRIPT
date         - date [YYYY-MM-DD HH:MM:SS]
echo         - echo [args]
sleep        - sleep seconds [nanoseconds]
id           - show uid, gid, euid, and egid
tty          - show ttyname
whoami       - show current user
logoff       - logoff from the system
setenv       - setenv [var] [string]
getenv       - getenv [var]
unsetenv     - unsetenv [var]
umask        - umask [new_umask]
rtc          - real time clock read and set

CONFIGURATION:

This command has no configuration.

3.2.2. alias - add alias for an existing command¶

SYNOPSYS:

alias oldCommand newCommand

DESCRIPTION:

This command adds an alternate name for an existing command to the command set.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

None.

EXAMPLES:

The following is an example of how to use alias:

SHLL [/] $ me
shell:me command not found
SHLL [/] $ alias whoami me
SHLL [/] $ me
rtems
SHLL [/] $ whoami
rtems

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_ALIAS to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_ALIAS when all shell commands have been configured.

PROGRAMMING INFORMATION:

The alias is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_alias(
    int    argc,
    char **argv
);

The configuration structure for the alias has the following prototype:

extern rtems_shell_cmd_t rtems_shell_ALIAS_Command;

3.2.3. cmdls - List commands¶

SYNOPSYS:

cmdls COMMAND...

DESCRIPTION:

This command lists the visible commands of the command set.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

The current user must have read permission to list a command.

EXAMPLES:

The following is an example of how to use cmdls:

SHLL [/] # cmdls help shutdown
r-xr-xr-x     0     0 help
r-x------     0     0 shutdown

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_CMDLS to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_CMDLS when all shell commands have been configured.

PROGRAMMING INFORMATION:

The configuration structure for the cmdls has the following prototype:

extern rtems_shell_cmd_t rtems_shell_CMDLS_Command;

3.2.4. cmdchown - Change user or owner of commands¶

SYNOPSYS:

cmdchown [OWNER][:[GROUP]] COMMAND...

DESCRIPTION:

This command changes the user or owner of a command.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

The current user must have an UID of zero or be the command owner to change the owner or group.

EXAMPLES:

The following is an example of how to use cmdchown:

[/] # cmdls help
r-xr-xr-x     0     0 help
[/] # cmdchown 1:1 help
[/] # cmdls help
r--r--r--     1     1 help

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_CMDCHOWN to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_CMDCHOWN when all shell commands have been configured.

PROGRAMMING INFORMATION:

The configuration structure for the cmdchown has the following prototype:

extern rtems_shell_cmd_t rtems_shell_CMDCHOWN_Command;

3.2.5. cmdchmod - Change mode of commands¶

SYNOPSYS:

cmdchmod OCTAL-MODE COMMAND...

DESCRIPTION:

This command changes the mode of a command.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

The current user must have an UID of zero or be the command owner to change the mode.

EXAMPLES:

The following is an example of how to use cmdchmod:

[/] # cmdls help
r-xr-xr-x     0     0 help
[/] # cmdchmod 544 help
[/] # cmdls help
r-xr--r--     0     0 help

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_CMDCHMOD to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_CMDCHMOD when all shell commands have been configured.

PROGRAMMING INFORMATION:

The configuration structure for the cmdchmod has the following prototype:

extern rtems_shell_cmd_t rtems_shell_CMDCHMOD_Command;

3.2.6. date - print or set current date and time¶

SYNOPSYS:

date
date DATE TIME

DESCRIPTION:

This command operates one of two modes. When invoked with no arguments, it prints the current date and time. When invoked with both date and time arguments, it sets the current time.

The date is specified in YYYY-MM-DD format. The time is specified in HH:MM:SS format.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

None.

EXAMPLES:

The following is an example of how to use date:

SHLL [/] $ date
Fri Jan  1 00:00:09 1988
SHLL [/] $ date 2008-02-29 06:45:32
SHLL [/] $ date
Fri Feb 29 06:45:35 2008

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_DATE to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_DATE when all shell commands have been configured.

PROGRAMMING INFORMATION:

The date is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_date(
    int    argc,
    char **argv
);

The configuration structure for the date has the following prototype:

extern rtems_shell_cmd_t rtems_shell_DATE_Command;

3.2.7. echo - produce message in a shell script¶

SYNOPSYS:

echo [-n | -e] args ...

DESCRIPTION:

Echo prints its arguments on the standard output, separated by spaces. Unless the -n option is present, a newline is output following the arguments. The -e option causes echo to treat the escape sequences specially, as described in the following paragraph. The -e option is the default, and is provided solely for compatibility with other systems. Only one of the options -n and -e may be given.

If any of the following sequences of characters is encountered during output, the sequence is not output. Instead, the specified action is performed:

b

A backspace character is output.

c

Subsequent output is suppressed. This is normally used at the end of the last argument to suppress the trailing newline that echo would otherwise output.

f

Output a form feed.

n

Output a newline character.

r

Output a carriage return.

t

Output a (horizontal) tab character.

v

Output a vertical tab.

0digits

Output the character whose value is given by zero to three digits. If there are zero digits, a nul character is output.

\

Output a backslash.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

The octal character escape mechanism (0digits) differs from the C language mechanism.

There is no way to force echo to treat its arguments literally, rather than interpreting them as options and escape sequences.

EXAMPLES:

The following is an example of how to use echo:

SHLL [/] $ echo a b c
a b c
SHLL [/] $ echo

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_ECHO to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_ECHO when all shell commands have been configured.

PROGRAMMING INFORMATION:

The echo is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_echo(
    int    argc,
    char **argv
);

The configuration structure for the echo has the following prototype:

extern rtems_shell_cmd_t rtems_shell_ECHO_Command;

ORIGIN:

The implementation and portions of the documentation for this command are from NetBSD 4.0.

3.2.8. sleep - delay for a specified amount of time¶

SYNOPSYS:

sleep seconds
sleep seconds nanoseconds

DESCRIPTION:

This command causes the task executing the shell to block for the specified number of seconds and nanoseconds.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

This command is implemented using the nanosleep() method.

The command line interface is similar to the sleep command found on POSIX systems but the addition of the nanoseconds parameter allows fine grained delays in shell scripts without adding another command such as usleep.

EXAMPLES:

The following is an example of how to use sleep:

SHLL [/] $ sleep 10
SHLL [/] $ sleep 0 5000000

It is not clear from the above but there is a ten second pause after executing the first command before the prompt is printed. The second command completes very quickly from a human perspective and there is no noticeable delay in the prompt being printed.

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_SLEEP to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_SLEEP when all shell commands have been configured.

PROGRAMMING INFORMATION:

The sleep is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_sleep(
    int    argc,
    char **argv
);

The configuration structure for the sleep has the following prototype:

extern rtems_shell_cmd_t rtems_shell_SLEEP_Command;

3.2.9. id - show uid gid euid and egid¶

SYNOPSYS:

id

DESCRIPTION:

This command prints the user identity. This includes the user id (uid), group id (gid), effective user id (euid), and effective group id (egid).

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

Remember there is only one POSIX process in a single processor RTEMS application. Each thread may have its own user identity and that identity is used by the filesystem to enforce permissions.

EXAMPLES:

The first example of the id command is from a session logged in as the normal user rtems:

SHLL [/] # id
uid=1(rtems),gid=1(rtems),euid=1(rtems),egid=1(rtems)

The second example of the id command is from a session logged in as the root user:

SHLL [/] # id
uid=0(root),gid=0(root),euid=0(root),egid=0(root)

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_ID to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_ID when all shell commands have been configured.

PROGRAMMING INFORMATION:

The id is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_id(
    int    argc,
    char **argv
);

The configuration structure for the id has the following prototype:

extern rtems_shell_cmd_t rtems_shell_ID_Command;

3.2.10. tty - show ttyname¶

SYNOPSYS:

tty

DESCRIPTION:

This command prints the file name of the device connected to standard input.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

NONE

EXAMPLES:

The following is an example of how to use tty:

SHLL [/] $ tty
/dev/console

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_TTY to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_TTY when all shell commands have been configured.

PROGRAMMING INFORMATION:

The tty is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_tty(
    int    argc,
    char **argv
);

The configuration structure for the tty has the following prototype:

extern rtems_shell_cmd_t rtems_shell_TTY_Command;

3.2.11. whoami - print effective user id¶

SYNOPSYS:

whoami

DESCRIPTION:

This command displays the user name associated with the current effective user id.

EXIT STATUS:

This command always succeeds.

NOTES:

None.

EXAMPLES:

The following is an example of how to use whoami:

SHLL [/] $ whoami
rtems

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_WHOAMI to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_WHOAMI when all shell commands have been configured.

PROGRAMMING INFORMATION:

The whoami is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_whoami(
    int    argc,
    char **argv
);

The configuration structure for the whoami has the following prototype:

extern rtems_shell_cmd_t rtems_shell_WHOAMI_Command;

3.2.12. getenv - print environment variable¶

SYNOPSYS:

getenv variable

DESCRIPTION:

This command is used to display the value of a variable in the set of environment variables.

EXIT STATUS:

This command will return 1 and print a diagnostic message if a failure occurs.

NOTES:

The entire RTEMS application shares a single set of environment variables.

EXAMPLES:

The following is an example of how to use getenv:

SHLL [/] $ getenv BASEPATH
/mnt/hda1

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_GETENV to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_GETENV when all shell commands have been configured.

PROGRAMMING INFORMATION:

The getenv is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_getenv(
    int    argc,
    char **argv
);

The configuration structure for the getenv has the following prototype:

extern rtems_shell_cmd_t rtems_shell_GETENV_Command;

3.2.13. setenv - set environment variable¶

SYNOPSYS:

setenv variable [value]

DESCRIPTION:

This command is used to add a new variable to the set of environment variables or to modify the variable of an already existing variable. If the value is not provided, the variable will be set to the empty string.

EXIT STATUS:

This command will return 1 and print a diagnostic message if a failure occurs.

NOTES:

The entire RTEMS application shares a single set of environment variables.

EXAMPLES:

The following is an example of how to use setenv:

SHLL [/] $ setenv BASEPATH /mnt/hda1

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_SETENV to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_SETENV when all shell commands have been configured.

PROGRAMMING INFORMATION:

The setenv is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_setenv(
    int    argc,
    char **argv
);

The configuration structure for the setenv has the following prototype:

extern rtems_shell_cmd_t rtems_shell_SETENV_Command;

3.2.14. unsetenv - unset environment variable¶

SYNOPSYS:

unsetenv variable

DESCRIPTION:

This command is remove to a variable from the set of environment variables.

EXIT STATUS:

This command will return 1 and print a diagnostic message if a failure occurs.

NOTES:

The entire RTEMS application shares a single set of environment variables.

EXAMPLES:

The following is an example of how to use unsetenv:

SHLL [/] $ unsetenv BASEPATH

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_UNSETENV to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_UNSETENV when all shell commands have been configured.

PROGRAMMING INFORMATION:

The unsetenv is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_unsetenv(
    int    argc,
    char **argv
);

The configuration structure for the unsetenv has the following prototype:

extern rtems_shell_cmd_t rtems_shell_UNSETENV_Command;

3.2.15. time - time command execution¶

SYNOPSYS:

time command [argument ...]

DESCRIPTION:

The time command executes and times a command. After the command finishes, time writes the total time elapsed. Times are reported in seconds.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

None.

EXAMPLES:

The following is an example of how to use time:

SHLL [/] $ time cp -r /nfs/directory /c

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_TIME to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_TIME when all shell commands have been configured.

PROGRAMMING INFORMATION:

The time is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_time(
    int    argc,
    char **argv
);

The configuration structure for the time has the following prototype:

extern rtems_shell_cmd_t rtems_shell_TIME_Command;

3.2.16. logoff - logoff from the system¶

SYNOPSYS:

logoff

DESCRIPTION:

This command logs the user out of the shell.

EXIT STATUS:

This command does not return.

NOTES:

The system behavior when the shell is exited depends upon how the shell was initiated. The typical behavior is that a login prompt will be displayed for the next login attempt or that the connection will be dropped by the RTEMS system.

EXAMPLES:

The following is an example of how to use logoff:

SHLL [/] $ logoff
logoff from the system...

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_LOGOFF to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_LOGOFF when all shell commands have been configured.

PROGRAMMING INFORMATION:

The logoff is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_logoff(
    int    argc,
    char **argv
);

The configuration structure for the logoff has the following prototype:

extern rtems_shell_cmd_t rtems_shell_LOGOFF_Command;

3.2.17. rtc - RTC driver configuration¶

SYNOPSYS:

rtc

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_RTC to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_RTC when all shell commands have been configured.

3.2.18. i2cdetect - detect I2C devices¶

SYNOPSYS:

i2cdetect <I2C_BUS>

DESCRIPTION:

Tries to detect I2C devices connected to the I2C bus. To do that, write requests with the length of 0 are used.

WARNING: This might confuse some I2C devices, so please use it only if you know what you are doing.

The command supports a -h option to get usage details.

The command works only with I2C bus drivers that use the Linux-Style API.

EXAMPLES:

The following is an example where two I2C devices are detected. One on 0x1a and one on 0x1f:

SHLL [/] # i2cdetect /dev/i2c1
    x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF
0x     -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
1x  -- -- -- -- -- -- -- -- -- -- 1a -- -- -- -- 1f
2x  -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
3x  -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
4x  -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
5x  -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
6x  -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
7x  -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
SHLL [/] #

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_I2CDETECT to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_I2CDETECT when all shell commands have been configured.

3.2.19. i2cget - get data from an EEPROM like I2C device¶

SYNOPSYS:

i2cget <I2C_BUS> <CHIP-ADDRESS> <DATA-ADDRESS> [<NR-BYTES>]

DESCRIPTION:

Get one or multiple bytes from an EEPROM like I2C device. If <NR-BYTES> is not given the command defaults to reading one byte. If you read multiple bytes (<NR-BYTES> given and bigger then 1) the read will be done in one single request. An auto incrementing register pointer is assumed.

The command supports a -h option to get usage details.

All numbers can be entered in decimal form (normal digits; e.g. 16), hexadecimal form (with 0x prefix; e.g. 0x10) or octal form (with a leading zero; e.g. 020).

The command works only with I2C bus drivers that use the Linux-Style API.

EXAMPLES:

The following is an example how to read a one byte register at 0xd from the I2C device at 0x1f:

SHLL [/] # i2cget /dev/i2c1 0x1f 0x0d
0xc7
SHLL [/] #

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_I2CGET to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_I2CGET when all shell commands have been configured.

3.2.20. i2cset - write data to an EEPROM like I2C device¶

SYNOPSYS:

i2cset <I2C_BUS> <CHIP-ADDRESS> <DATA-ADDRESS> <VALUE> [<VALUE> [...]]

DESCRIPTION:

Write one or multiple bytes to an EEPROM like I2C device. If you write multiple bytes (multiple <VALUE> given) the write will be done in one single request. An auto incrementing register pointer is assumed.

The command supports a -h option to get usage details.

All numbers can be entered in decimal form (normal digits; e.g. 16), hexadecimal form (with 0x prefix; e.g. 0x10) or octal form (with a leading zero; e.g. 020).

The command works only with I2C bus drivers that use the Linux-Style API.

EXAMPLES:

The following is an example how to write one byte of 0x00 to the register at 0x11 of the I2C device at 0x1f:

SHLL [/] # i2cset /dev/i2c1 0x1f 0x11 0x00
SHLL [/] #

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_I2CSET to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_I2CSET when all shell commands have been configured.

3.2.21. spi - read and write simple data to an SPI bus¶

SYNOPSYS:

spi [-loh] [-c <cs>] [-s <speed>] [-m <mode>] <SPI_BUS> xx [xx [..]]

DESCRIPTION:

Write data to an SPI bus and read the responses.

The command supports a -h option to get usage details.

The data bytes (xx in the SYNOPSIS) are in hexadecimal form (e.g. 0x10 or 10 both have a value of decimal 16). This allows longer hex strings before the shell input limit is reached. All other numbers can be entered in decimal form (normal digits; e.g. 16), hexadecimal form (with 0x prefix; e.g. 0x10) or octal form (with a leading zero; e.g. 020).

The command works only with SPI bus drivers that use the Linux-Style API.

EXAMPLES:

The following is an example how to write multiple bytes (0x4a 0x4b 0x4c) to the bus. The response is 0xa1 0xa2 0xa3 in this case. Chip select 1 will be used.

SHLL [/] # spi /dev/spi1 -c 1 4a 4b 4c
received: a1 a2 a3
SHLL [/] #

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_SPI to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_SPI when all shell commands have been configured.

3.2.22. exit - exit the shell¶

SYNOPSYS:

exit

DESCRIPTION:

This command causes the shell interpreter to exit.

EXIT STATUS:

This command does not return.

NOTES:

In contrast to logoff - logoff from the system, this command is built into the shell interpreter loop.

EXAMPLES:

The following is an example of how to use exit:

SHLL [/] $ exit
Shell exiting

CONFIGURATION:

This command is always present and cannot be disabled.

PROGRAMMING INFORMATION:

The exit is implemented directly in the shell interpreter. There is no C routine associated with it.

4.2.1. blksync - sync the block driver¶

SYNOPSYS:

blksync driver

DESCRIPTION:

This command issues a block driver sync call to the driver. The driver is a path to a device node. The sync call will flush all pending writes in the cache to the media and block until the writes have completed.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

None.

EXAMPLES:

The following is an example of how to use blksync:

blksync /dev/hda1

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_BLKSYNC to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_BLKSYNC when all shell commands have been configured.

PROGRAMMING INFORMATION:

The blksync is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_blksync(
    int    argc,
    char **argv
);

The configuration structure for the blksync has the following prototype:

extern rtems_shell_cmd_t rtems_shell_BLKSYNC_Command;

4.2.2. cat - display file contents¶

SYNOPSYS:

cat file1 [file2 .. fileN]

DESCRIPTION:

This command displays the contents of the specified files.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

It is possible to read the input from a device file using cat.

EXAMPLES:

The following is an example of how to use cat:

SHLL [/] # cat /etc/passwd
root:*:0:0:root::/:/bin/sh
rtems:*:1:1:RTEMS Application::/:/bin/sh
tty:!:2:2:tty owner::/:/bin/false

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_CAT to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_CAT when all shell commands have been configured.

PROGRAMMING INFORMATION:

The cat is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_cat(
    int    argc,
    char **argv
);

The configuration structure for the cat has the following prototype:

extern rtems_shell_cmd_t rtems_shell_CAT_Command;

4.2.3. cd - alias for chdir¶

SYNOPSYS:

cd directory

DESCRIPTION:

This command is an alias or alternate name for the chdir. See ls - list files in the directory for more information.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

None.

EXAMPLES:

The following is an example of how to use cd:

SHLL [/] $ cd etc
SHLL [/etc] $ cd /
SHLL [/] $ cd /etc
SHLL [/etc] $ pwd
/etc
SHLL [/etc] $ cd /
SHLL [/] $ pwd
/
SHLL [/] $ cd etc
SHLL [/etc] $ cd ..
SHLL [/] $ pwd
/

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_CD to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_CD when all shell commands have been configured.

PROGRAMMING INFORMATION:

The cd is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_cd(
    int    argc,
    char **argv
);

The configuration structure for the cd has the following prototype:

extern rtems_shell_cmd_t rtems_shell_CD_Command;

4.2.4. chdir - change the current directory¶

SYNOPSYS:

chdir [dir]

DESCRIPTION:

This command is used to change the current working directory to the specified directory. If no arguments are given, the current working directory will be changed to /.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

None.

EXAMPLES:

The following is an example of how to use chdir:

SHLL [/] $ pwd
/
SHLL [/] $ chdir etc
SHLL [/etc] $ pwd
/etc

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_CHDIR to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_CHDIR when all shell commands have been configured.

PROGRAMMING INFORMATION:

The chdir is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_chdir(
    int    argc,
    char **argv
);

The configuration structure for the chdir has the following prototype:

extern rtems_shell_cmd_t rtems_shell_CHDIR_Command;

4.2.5. chmod - change permissions of a file¶

SYNOPSYS:

chmod permissions file1 [file2...]

DESCRIPTION:

This command changes the permissions on the files specified to the indicated permissions. The permission values are POSIX based with owner, group, and world having individual read, write, and executive permission bits.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

The chmod command only takes numeric representations of the permissions.

EXAMPLES:

The following is an example of how to use chmod:

SHLL [/] # cd etc
SHLL [/etc] # ls
-rw-r--r--   1   root   root         102 Jan 01 00:00 passwd
-rw-r--r--   1   root   root          42 Jan 01 00:00 group
-rw-r--r--   1   root   root          30 Jan 01 00:00 issue
-rw-r--r--   1   root   root          28 Jan 01 00:00 issue.net
4 files 202 bytes occupied
SHLL [/etc] # chmod 0777 passwd
SHLL [/etc] # ls
-rwxrwxrwx   1   root   root         102 Jan 01 00:00 passwd
-rw-r--r--   1   root   root          42 Jan 01 00:00 group
-rw-r--r--   1   root   root          30 Jan 01 00:00 issue
-rw-r--r--   1   root   root          28 Jan 01 00:00 issue.net
4 files 202 bytes occupied
SHLL [/etc] # chmod 0322 passwd
SHLL [/etc] # ls
--wx-w--w-   1 nouser   root         102 Jan 01 00:00 passwd
-rw-r--r--   1 nouser   root          42 Jan 01 00:00 group
-rw-r--r--   1 nouser   root          30 Jan 01 00:00 issue
-rw-r--r--   1 nouser   root          28 Jan 01 00:00 issue.net
4 files 202 bytes occupied
SHLL [/etc] # chmod 0644 passwd
SHLL [/etc] # ls
-rw-r--r--   1   root   root         102 Jan 01 00:00 passwd
-rw-r--r--   1   root   root          42 Jan 01 00:00 group
-rw-r--r--   1   root   root          30 Jan 01 00:00 issue
-rw-r--r--   1   root   root          28 Jan 01 00:00 issue.net
4 files 202 bytes occupied

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_CHMOD to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_CHMOD when all shell commands have been configured.

PROGRAMMING INFORMATION:

The chmod is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_chmod(
    int    argc,
    char **argv
);

The configuration structure for the chmod has the following prototype:

extern rtems_shell_cmd_t rtems_shell_CHMOD_Command;

4.2.6. chroot - change the root directory¶

SYNOPSYS:

chroot [dir]

DESCRIPTION:

This command changes the root directory to dir for subsequent commands.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

The destination directory dir must exist.

NOTES:

None.

EXAMPLES:

The following is an example of how to use chroot and the impact it has on the environment for subsequent command invocations:

SHLL [/] $ cat passwd
cat: passwd: No such file or directory
SHLL [/] $ chroot etc
SHLL [/] $ cat passwd
root:*:0:0:root::/:/bin/sh
rtems:*:1:1:RTEMS Application::/:/bin/sh
tty:!:2:2:tty owner::/:/bin/false
SHLL [/] $ cat /etc/passwd
cat: /etc/passwd: No such file or directory

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_CHROOT to have this command included. Additional to that you have to add one POSIX key value pair for each thread where you want to use the command.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_CHROOT when all shell commands have been configured.

PROGRAMMING INFORMATION:

The chroot is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_chroot(
    int    argc,
    char **argv
);

The configuration structure for the chroot has the following prototype:

extern rtems_shell_cmd_t rtems_shell_CHROOT_Command;

4.2.7. cp - copy files¶

SYNOPSYS:

cp [-R [-H | -L | -P]] [-f | -i] [-pv] src target
cp [-R [-H | -L] ] [-f | -i] [-NpPv] source_file ... target_directory

DESCRIPTION:

In the first synopsis form, the cp utility copies the contents of the source_file to the target_file. In the second synopsis form, the contents of each named source_file is copied to the destination target_directory. The names of the files themselves are not changed. If cp detects an attempt to copy a file to itself, the copy will fail.

The following options are available:

-f

For each existing destination pathname, attempt to overwrite it. If permissions do not allow copy to succeed, remove it and create a new file, without prompting for confirmation. (The -i option is ignored if the -f option is specified.)

-H

If the -R option is specified, symbolic links on the command line are followed. (Symbolic links encountered in the tree traversal are not followed.)

-i

Causes cp to write a prompt to the standard error output before copying a file that would overwrite an existing file. If the response from the standard input begins with the character ‘y’, the file copy is attempted.

-L

If the -R option is specified, all symbolic links are followed.

-N

When used with -p, do not copy file flags.

-P

No symbolic links are followed.

-p

Causes cp to preserve in the copy as many of the modification time, access time, file flags, file mode, user ID, and group ID as allowed by permissions. If the user ID and group ID cannot be preserved, no error message is displayed and the exit value is not altered. If the source file has its set user ID bit on and the user ID cannot be preserved, the set user ID bit is not preserved in the copy’s permissions. If the source file has its set group ID bit on and the group ID cannot be preserved, the set group ID bit is not preserved in the copy’s permissions. If the source file has both its set user ID and set group ID bits on, and either the user ID or group ID cannot be preserved, neither the set user ID or set group ID bits are preserved in the copy’s permissions.

-R

If source_file designates a directory, cp copies the directory and the entire subtree connected at that point. This option also causes symbolic links to be copied, rather than indirected through, and for cp to create special files rather than copying them as normal files. Created directories have the same mode as the corresponding source directory, unmodified by the process’s umask.

-v

Cause cp to be verbose, showing files as they are copied.

For each destination file that already exists, its contents are overwritten if permissions allow, but its mode, user ID, and group ID are unchanged.

In the second synopsis form, target_directory must exist unless there is only one named source_file which is a directory and the -R flag is specified.

If the destination file does not exist, the mode of the source file is used as modified by the file mode creation mask (umask, see csh(1)). If the source file has its set user ID bit on, that bit is removed unless both the source file and the destination file are owned by the same user. If the source file has its set group ID bit on, that bit is removed unless both the source file and the destination file are in the same group and the user is a member of that group. If both the set user ID and set group ID bits are set, all of the above conditions must be fulfilled or both bits are removed.

Appropriate permissions are required for file creation or overwriting.

Symbolic links are always followed unless the -R flag is set, in which case symbolic links are not followed, by default. The -H or -L flags (in conjunction with the -R flag), as well as the -P flag cause symbolic links to be followed as described above. The -H and -L options are ignored unless the -R option is specified. In addition, these options override eachsubhedading other and the command’s actions are determined by the last one specified.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

NONE

EXAMPLES:

The following is an example of how to use cp to copy a file to a new name in the current directory:

SHLL [/] # cat joel
cat: joel: No such file or directory
SHLL [/] # cp etc/passwd joel
SHLL [/] # cat joel
root:*:0:0:root::/:/bin/sh
rtems:*:1:1:RTEMS Application::/:/bin/sh
tty:!:2:2:tty owner::/:/bin/false
SHLL [/] # ls
drwxr-xr-x   1   root   root         536 Jan 01 00:00 dev/
drwxr-xr-x   1   root   root        1072 Jan 01 00:00 etc/
-rw-r--r--   1   root   root         102 Jan 01 00:00 joel
3 files 1710 bytes occupied

The following is an example of how to use cp to copy one or more files to a destination directory and use the same basename in the destination directory:

SHLL [/] # mkdir tmp
SHLL [/] # ls tmp
0 files 0 bytes occupied
SHLL [/] # cp /etc/passwd tmp
SHLL [/] # ls /tmp
-rw-r--r--   1   root   root         102 Jan 01 00:01 passwd
1 files 102 bytes occupied
SHLL [/] # cp /etc/passwd /etc/group /tmp
SHLL [/] # ls /tmp
-rw-r--r--   1   root   root         102 Jan 01 00:01 passwd
-rw-r--r--   1   root   root          42 Jan 01 00:01 group
2 files 144 bytes occupied
SHLL [/] #

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define``CONFIGURE_SHELL_COMMAND_CP`` to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_CP when all shell commands have been configured.

PROGRAMMING INFORMATION:

The cp command is implemented by a C language function which has the following prototype:

int rtems_shell_main_cp(
    int    argc,
    char **argv
);

The configuration structure for the cp has the following prototype:

extern rtems_shell_cmd_t rtems_shell_CP_Command;

ORIGIN:

The implementation and portions of the documentation for this command are from NetBSD 4.0.

4.2.8. dd - convert and copy a file¶

SYNOPSYS:

dd [operands ...]

DESCRIPTION:

The dd utility copies the standard input to the standard output. Input data is read and written in 512-byte blocks. If input reads are short, input from multiple reads are aggregated to form the output block. When finished, dd displays the number of complete and partial input and output blocks and truncated input records to the standard error output.

The following operands are available:

bs=n

Set both input and output block size, superseding the ibs and obs operands. If no conversion values other than noerror, notrunc or sync are specified, then each input block is copied to the output as a single block without any aggregation of short blocks.

cbs=n

Set the conversion record size to n bytes. The conversion record size is required by the record oriented conversion values.

count=n

Copy only n input blocks.

files=n

Copy n input files before terminating. This operand is only applicable when the input device is a tape.

ibs=n

Set the input block size to n bytes instead of the default 512.

if=file

Read input from file instead of the standard input.

obs=n

Set the output block size to n bytes instead of the default 512.

of=file

Write output to file instead of the standard output. Any regular output file is truncated unless the notrunc conversion value is specified. If an initial portion of the output file is skipped (see the seek operand) the output file is truncated at that point.

seek=n

Seek n blocks from the beginning of the output before copying. On non-tape devices, a lseek operation is used. Otherwise, existing blocks are read and the data discarded. If the seek operation is past the end of file, space from the current end of file to the specified offset is filled with blocks of NUL bytes.

skip=n

Skip n blocks from the beginning of the input before copying. On input which supports seeks, a lseek operation is used. Otherwise, input data is read and discarded. For pipes, the correct number of bytes is read. For all other devices, the correct number of blocks is read without distinguishing between a partial or complete block being read.

progress=n

Switch on display of progress if n is set to any non-zero value. This will cause a “.” to be printed (to the standard error output) for every n full or partial blocks written to the output file.

conv=value[,value…]

Where value is one of the symbols from the following list.

ascii, oldascii

The same as the unblock value except that characters are translated from EBCDIC to ASCII before the records are converted. (These values imply unblock if the operand cbs is also specified.) There are two conversion maps for ASCII. The value ascii specifies the recom- mended one which is compatible with AT&T System V UNIX. The value oldascii specifies the one used in historic AT&T and pre 4.3BSD-Reno systems.

block

Treats the input as a sequence of newline or end-of-file terminated variable length records independent of input and output block boundaries. Any trailing newline character is discarded. Each input record is converted to a fixed length output record where the length is specified by the cbs operand. Input records shorter than the conversion record size are padded with spaces. Input records longer than the conversion record size are truncated. The number of truncated input records, if any, are reported to the standard error output at the completion of the copy.

ebcdic, ibm, oldebcdic, oldibm

The same as the block value except that characters are translated from ASCII to EBCDIC after the records are converted. (These values imply block if the operand cbs is also specified.) There are four conversion maps for EBCDIC. The value ebcdic specifies the recommended one which is compatible with AT&T System V UNIX. The value ibm is a slightly different mapping, which is compatible with the AT&T System V UNIX ibm value. The values oldebcdic and oldibm are maps used in historic AT&T and pre 4.3BSD-Reno systems.

lcase

Transform uppercase characters into lowercase characters.

noerror

Do not stop processing on an input error. When an input error occurs, a diagnostic message followed by the current input and output block counts will be written to the standard error output in the same format as the standard completion message. If the sync conversion is also specified, any missing input data will be replaced with NUL bytes (or with spaces if a block oriented conversion value was specified) and processed as a normal input buffer. If the sync conversion is not specified, the input block is omitted from the output. On input files which are not tapes or pipes, the file offset will be positioned past the block in which the error occurred using lseek(2).

notrunc

Do not truncate the output file. This will preserve any blocks in the output file not explicitly written by dd. The notrunc value is not supported for tapes.

osync

Pad the final output block to the full output block size. If the input file is not a multiple of the output block size after conversion, this conversion forces the final output block to be the same size as preceding blocks for use on devices that require regularly sized blocks to be written. This option is incompatible with use of the bs=n block size specification.

sparse

If one or more non-final output blocks would consist solely of NUL bytes, try to seek the output file by the required space instead of filling them with NULs. This results in a sparse file on some file systems.

swab

Swap every pair of input bytes. If an input buffer has an odd number of bytes, the last byte will be ignored during swapping.

sync

Pad every input block to the input buffer size. Spaces are used for pad bytes if a block oriented conversion value is specified, otherwise NUL bytes are used.

ucase

Transform lowercase characters into uppercase characters.

unblock

Treats the input as a sequence of fixed length records independent of input and output block boundaries. The length of the input records is specified by the cbs operand. Any trailing space characters are discarded and a newline character is appended.

Where sizes are specified, a decimal number of bytes is expected. Two or more numbers may be separated by an “x” to indicate a product. Each number may have one of the following optional suffixes:

b

Block; multiply by 512

k

Kibi; multiply by 1024 (1 KiB)

m

Mebi; multiply by 1048576 (1 MiB)

g

Gibi; multiply by 1073741824 (1 GiB)

t

Tebi; multiply by 1099511627776 (1 TiB)

w

Word; multiply by the number of bytes in an integer

When finished, dd displays the number of complete and partial input and output blocks, truncated input records and odd-length byte-swapping ritten. Partial output blocks to tape devices are considered fatal errors. Otherwise, the rest of the block will be written. Partial output blocks to character devices will produce a warning message. A truncated input block is one where a variable length record oriented conversion value was specified and the input line was too long to fit in the conversion record or was not newline terminated.

Normally, data resulting from input or conversion or both are aggregated into output blocks of the specified size. After the end of input is reached, any remaining output is written as a block. This means that the final output block may be shorter than the output block size.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

NONE

EXAMPLES:

The following is an example of how to use dd:

SHLL [/] $ dd if=/nfs/boot-image of=/dev/hda1

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_DD to have this command included.

This command can be excluded from the shell command set by defining``CONFIGURE_SHELL_NO_COMMAND_DD`` when all shell commands have been configured.

PROGRAMMING INFORMATION:

The dd command is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_dd(
    int    argc,
    char **argv
);

The configuration structure for the dd has the following prototype:

extern rtems_shell_cmd_t rtems_shell_DD_Command;

4.2.9. debugrfs - debug RFS file system¶

SYNOPSYS:

debugrfs [-hl] path command [options]

DESCRIPTION:

The command provides debugging information for the RFS file system.

The options are:

-h

Print a help message.

-l

List the commands.

path

Path to the mounted RFS file system. The file system has to be mounted to view to use this command.

The commands are:

block start [end]

Display the contents of the blocks from start to end.

data

Display the file system data and configuration.

dir bno

Process the block as a directory displaying the entries.

group start [end]

Display the group data from the start group to the end group.

inode [-aef] [start] [end]

Display the inodes between start and end. If no start and end is provides all inodes are displayed.

-a

Display all inodes. That is allocated and unallocated inodes.

-e

Search and display on inodes that have an error.

-f

Force display of inodes, even when in error.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

NONE

EXAMPLES:

The following is an example of how to use debugrfs:

SHLL [/] $ debugrfs /c data

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_DEBUGRFS to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_DEBUGRFS when all shell commands have been configured.

PROGRAMMING INFORMATION:

The debugrfs command is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_debugrfs(
    int    argc,
    char **argv
);

The configuration structure for debugrfs has the following prototype:

extern rtems_shell_cmd_t rtems_shell_DEBUGRFS_Command;

4.2.10. df - display file system disk space usage¶

SYNOPSYS:

df [-h] [-B block_size]

DESCRIPTION:

This command print disk space usage for mounted file systems.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

NONE

EXAMPLES:

The following is an example of how to use df:

SHLL [/] $ df -B 4K
Filesystem     4K-blocks        Used   Available       Use%     Mounted on
/dev/rda               124         1         124         0%   /mnt/ramdisk
SHLL [/] $ df
Filesystem     1K-blocks        Used   Available       Use%     Mounted on
/dev/rda               495         1         494         0%   /mnt/ramdisk
SHLL [/] $ df -h
Filesystem     Size             Used   Available       Use%     Mounted on
/dev/rda              495K        1K        494K         0%   /mnt/ramdisk

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_DF to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_DF when all shell commands have been configured.

PROGRAMMING INFORMATION:

The df is implemented by a C language function which has the following prototype:

int rtems_shell_main_df(
    int    argc,
    char **argv
);

The configuration structure for the df has the following prototype:

extern rtems_shell_cmd_t rtems_shell_DF_Command;

4.2.11. dir - alias for ls¶

SYNOPSYS:

dir [dir]

DESCRIPTION:

This command is an alias or alternate name for the ls. See ls - list files in the directory for more information.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

NONE

EXAMPLES:

The following is an example of how to use dir:

SHLL [/] $ dir
drwxr-xr-x   1   root   root         536 Jan 01 00:00 dev/
drwxr-xr-x   1   root   root        1072 Jan 01 00:00 etc/
2 files 1608 bytes occupied
SHLL [/] $ dir etc
-rw-r--r--   1   root   root         102 Jan 01 00:00 passwd
-rw-r--r--   1   root   root          42 Jan 01 00:00 group
-rw-r--r--   1   root   root          30 Jan 01 00:00 issue
-rw-r--r--   1   root   root          28 Jan 01 00:00 issue.net
4 files 202 bytes occupied

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define``CONFIGURE_SHELL_COMMAND_DIR`` to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_DIR when all shell commands have been configured.

PROGRAMMING INFORMATION:

The dir is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_dir(
    int    argc,
    char **argv
);

The configuration structure for the dir has the following prototype:

extern rtems_shell_cmd_t rtems_shell_DIR_Command;

4.2.12. fdisk - format disk¶

SYNOPSYS:

fdisk

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_FDISK to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_FDISK when all shell commands have been configured.

4.2.13. hexdump - ascii/dec/hex/octal dump¶

SYNOPSYS:

hexdump [-bcCdovx] [-e format_string] [-f format_file] [-n length] [-s skip] file ...

DESCRIPTION:

The hexdump utility is a filter which displays the specified files, or the standard input, if no files are specified, in a user specified format.

The options are as follows:

-b

One-byte octal display. Display the input offset in hexadecimal, followed by sixteen space-separated, three column, zero-filled, bytes of input data, in octal, per line.

-c

One-byte character display. Display the input offset in hexadecimal, followed by sixteen space-separated, three column, space-filled, characters of input data per line.

-C

Canonical hex+ASCII display. Display the input offset in hexadecimal, followed by sixteen space-separated, two column, hexadecimal bytes, followed by the same sixteen bytes in %_p format enclosed in “|” characters.

-d

Two-byte decimal display. Display the input offset in hexadecimal, followed by eight space-separated, five column, zero-filled, two-byte units of input data, in unsigned decimal, per line.

-e format_string

Specify a format string to be used for displaying data.

-f format_file

Specify a file that contains one or more newline separated format strings. Empty lines and lines whose first non-blank character is a hash mark (#) are ignored.

-n length

Interpret only length bytes of input.

-o

Two-byte octal display. Display the input offset in hexadecimal, followed by eight space-separated, six column, zerofilled, two byte quantities of input data, in octal, per line.

-s offset

Skip offset bytes from the beginning of the input. By default, offset is interpreted as a decimal number. With a leading 0x or 0X, offset is interpreted as a hexadecimal number, otherwise, with a leading 0, offset is interpreted as an octal number. Appending the character b, k, or m to offset causes it to be interpreted as a multiple of 512, 1024, or 1048576, respectively.

-v

The -v option causes hexdump to display all input data. Without the -v option, any number of groups of output lines, which would be identical to the immediately preceding group of output lines (except for the input offsets), are replaced with a line containing a single asterisk.

-x

Two-byte hexadecimal display. Display the input offset in hexadecimal, followed by eight, space separated, four column, zero-filled, two-byte quantities of input data, in hexadecimal, per line.

For each input file, hexdump sequentially copies the input to standard output, transforming the data according to the format strings specified by the -e and -f options, in the order that they were specified.

Formats

A format string contains any number of format units, separated by whitespace. A format unit contains up to three items: an iteration count, a byte count, and a format.

The iteration count is an optional positive integer, which defaults to one. Each format is applied iteration count times.

The byte count is an optional positive integer. If specified it defines the number of bytes to be interpreted by each iteration of the format.

If an iteration count and/or a byte count is specified, a single slash must be placed after the iteration count and/or before the byte count to disambiguate them. Any whitespace before or after the slash is ignored.

The format is required and must be surrounded by double quote (” “) marks. It is interpreted as a fprintf-style format string (see*fprintf*), with the following exceptions:

• An asterisk (*) may not be used as a field width or precision.

• A byte count or field precision is required for each “s” con- version character (unlike the fprintf(3) default which prints the entire string if the precision is unspecified).

• The conversion characters “h”, “l”, “n”, “p” and “q” are not supported.

• The single character escape sequences described in the C standard are supported:

  NUL 0 <alert character> a <backspace> b <form-feed> f <newline> n <carriage return> r <tab> t <vertical tab> v

Hexdump also supports the following additional conversion strings:

_a[dox]

Display the input offset, cumulative across input files, of the next byte to be displayed. The appended characters d, o, and x specify the display base as decimal, octal or hexadecimal respectively.

_A[dox]

Identical to the _a conversion string except that it is only performed once, when all of the input data has been processed.

_c

Output characters in the default character set. Nonprinting characters are displayed in three character, zero-padded octal, except for those representable by standard escape notation (see above), which are displayed as two character strings.

_p

Output characters in the default character set. Nonprinting characters are displayed as a single “.”.

_u

Output US ASCII characters, with the exception that control characters are displayed using the following, lower-case, names. Characters greater than 0xff, hexadecimal, are displayed as hexadecimal strings.

000 nul	001 soh	002 stx	003 etx	004 eot	005 enq
006 ack	007 bel	008 bs	009 ht	00A lf	00B vt
00C ff	00D cr	00E so	00F si	010 dle	011 dc1
012 dc2	013 dc3	014 dc4	015 nak	016 syn	017 etb
018 can	019 em	01A sub	01B esc	01C fs	01D gs
01E rs	01F us	07F del

The default and supported byte counts for the conversion characters are as follows:

%_c, %_p, %_u, %c	One byte counts only.
%d, %i, %o, %u, %X, %x	Four byte default, one, two, four and eight byte counts supported.
%E, %e, %f, %G, %g	Eight byte default, four byte counts supported.

The amount of data interpreted by each format string is the sum of the data required by each format unit, which is the iteration count times the byte count, or the iteration count times the number of bytes required by the format if the byte count is not specified.

The input is manipulated in “blocks”, where a block is defined as the largest amount of data specified by any format string. Format strings interpreting less than an input block’s worth of data, whose last format unit both interprets some number of bytes and does not have a specified iteration count, have the iteration count incremented until the entire input block has been processed or there is not enough data remaining in the block to satisfy the format string.

If, either as a result of user specification or hexdump modifying the iteration count as described above, an iteration count is greater than one, no trailing whitespace characters are output during the last iteration.

It is an error to specify a byte count as well as multiple conversion characters or strings unless all but one of the conversion characters or strings is _a or _A.

If, as a result of the specification of the -n option or end-of-file being reached, input data only partially satisfies a format string, the input block is zero-padded sufficiently to display all available data (i.e. any format units overlapping the end of data will display some num- ber of the zero bytes).

Further output by such format strings is replaced by an equivalent number of spaces. An equivalent number of spaces is defined as the number of spaces output by an s conversion character with the same field width and precision as the original conversion character or conversion string but with any “+”, “ “, “#” conversion flag characters removed, and ref- erencing a NULL string.

If no format strings are specified, the default display is equivalent to specifying the -x option.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

NONE

EXAMPLES:

The following is an example of how to use hexdump:

SHLL [/] $ hexdump -C -n 512 /dev/hda1

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_HEXDUMP to have this command included.

This command can be excluded from the shell command set by defining``CONFIGURE_SHELL_NO_COMMAND_HEXDUMP`` when all shell commands have been configured.

PROGRAMMING INFORMATION:

The hexdump command is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_hexdump(
    int    argc,
    char **argv
);

The configuration structure for the hexdump has the following prototype:

extern rtems_shell_cmd_t rtems_shell_HEXDUMP_Command;

4.2.14. ln - make links¶

SYNOPSYS:

ln [-fhinsv] source_file [target_file]
ln [-fhinsv] source_file ... target_dir

DESCRIPTION:

The ln utility creates a new directory entry (linked file) which has the same modes as the original file. It is useful for maintaining multiple copies of a file in many places at once without using up storage for the “copies”; instead, a link “points” to the original copy. There are two types of links; hard links and symbolic links. How a link “points” to a file is one of the differences between a hard or symbolic link.

The options are as follows:

-f

Unlink any already existing file, permitting the link to occur.

-h

If the target_file or target_dir is a symbolic link, do not follow it. This is most useful with the -f option, to replace a symlink which may point to a directory.

-i

Cause ln to write a prompt to standard error if the target file exists. If the response from the standard input begins with the character ‘y’ or ‘Y’, then unlink the target file so that the link may occur. Otherwise, do not attempt the link. (The -i option overrides any previous -f options.)

-n

Same as -h, for compatibility with other ln implementations.

-s

Create a symbolic link.

-v

Cause ln to be verbose, showing files as they are processed.

By default ln makes hard links. A hard link to a file is indistinguishable from the original directory entry; any changes to a file are effective independent of the name used to reference the file. Hard links may not normally refer to directories and may not span file systems.

A symbolic link contains the name of the file to which it is linked. The referenced file is used when an open operation is performed on the link. A stat on a symbolic link will return the linked-to file; an lstat must be done to obtain information about the link. The readlink call may be used to read the contents of a symbolic link. Symbolic links may span file systems and may refer to directories.

Given one or two arguments, ln creates a link to an existing file source_file. If target_file is given, the link has that name; target_file may also be a directory in which to place the link; otherwise it is placed in the current directory. If only the directory is specified, the link will be made to the last component of source_file.

Given more than two arguments, ln makes links in target_dir to all the named source files. The links made will have the same name as the files being linked to.

EXIT STATUS:

The ln utility exits 0 on success, and >0 if an error occurs.

NOTES:

None.

EXAMPLES:

SHLL [/] ln -s /dev/console /dev/con1

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_LN to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_LN when all shell commands have been configured.

PROGRAMMING INFORMATION:

The ln command is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_ln(
    int    argc,
    char **argv
);

The configuration structure for the ln has the following prototype:

extern rtems_shell_cmd_t rtems_shell_LN_Command;

ORIGIN:

The implementation and portions of the documentation for this command are from NetBSD 4.0.

4.2.15. ls - list files in the directory¶

SYNOPSYS:

ls [dir]

DESCRIPTION:

This command displays the contents of the specified directory. If no arguments are given, then it displays the contents of the current working directory.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

This command currently does not display information on a set of files like the POSIX ls(1). It only displays the contents of entire directories.

EXAMPLES:

The following is an example of how to use ls:

SHLL [/] $ ls
drwxr-xr-x   1   root   root         536 Jan 01 00:00 dev/
drwxr-xr-x   1   root   root        1072 Jan 01 00:00 etc/
2 files 1608 bytes occupied
SHLL [/] $ ls etc
-rw-r--r--   1   root   root         102 Jan 01 00:00 passwd
-rw-r--r--   1   root   root          42 Jan 01 00:00 group
-rw-r--r--   1   root   root          30 Jan 01 00:00 issue
-rw-r--r--   1   root   root          28 Jan 01 00:00 issue.net
4 files 202 bytes occupied
SHLL [/] $ ls dev etc
-rwxr-xr-x   1  rtems   root           0 Jan 01 00:00 console
-rwxr-xr-x   1   root   root           0 Jan 01 00:00 console_b

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_LS to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_LS when all shell commands have been configured.

PROGRAMMING INFORMATION:

The ls is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_ls(
    int    argc,
    char **argv
);

The configuration structure for the ls has the following prototype:

extern rtems_shell_cmd_t rtems_shell_LS_Command;

4.2.16. md5 - compute the Md5 hash of a file or list of files¶

SYNOPSYS:

md5 <files>

DESCRIPTION:

This command prints the MD5 of a file. You can provide one or more files on the command line and a hash for each file is printed in a single line of output.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

None.

EXAMPLES:

The following is an example of how to use md5:

SHLL [/] $ md5 shell-init
MD5 (shell-init) = 43b4d2e71b47db79eae679a2efeacf31

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define``CONFIGURE_SHELL_COMMAND_MD5`` to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_MD5 when all shell commands have been configured.

PROGRAMMING INFORMATION:

The md5 is implemented by a C language function which has the following prototype:

int rtems_shell_main_md5(
    int    argc,
    char **argv
);

The configuration structure for the md5 has the following prototype:

extern rtems_shell_cmd_t rtems_shell_MD5_Command;

4.2.17. mkdir - create a directory¶

SYNOPSYS:

mkdir  dir [dir1 .. dirN]

DESCRIPTION:

This command creates the set of directories in the order they are specified on the command line. If an error is encountered making one of the directories, the command will continue to attempt to create the remaining directories on the command line.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

If this command is invoked with no arguments, nothing occurs.

The user must have sufficient permissions to create the directory. For the fileio test provided with RTEMS, this means the user must login as root not rtems.

EXAMPLES:

The following is an example of how to use mkdir:

SHLL [/] # ls
drwxr-xr-x   1   root   root         536 Jan 01 00:00 dev/
drwxr-xr-x   1   root   root        1072 Jan 01 00:00 etc/
2 files 1608 bytes occupied
SHLL [/] # mkdir joel
SHLL [/] # ls joel
0 files 0 bytes occupied
SHLL [/] # cp etc/passwd joel
SHLL [/] # ls joel
-rw-r--r--   1   root   root         102 Jan 01 00:02 passwd
1 files 102 bytes occupied

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_MKDIR to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_MKDIR when all shell commands have been configured.

PROGRAMMING INFORMATION:

The mkdir is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_mkdir(
    int    argc,
    char **argv
);

The configuration structure for the mkdir has the following prototype:

extern rtems_shell_cmd_t rtems_shell_MKDIR_Command;

4.2.18. mkdos - DOSFS file system format¶

SYNOPSYS:

mkdos [-V label] [-s sectors/cluster] [-r size] [-v] path

DESCRIPTION:

This command formats a block device entry with the DOSFS file system.

-V label

Specify the volume label.

-s sectors/cluster

Specify the number of sectors per cluster.

-r size

Specify the number of entries in the root directory.

-v

Enable verbose output mode.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

None.

EXAMPLES:

The following is an example of how to use mkdos:

SHLL [/] $ mkdos /dev/rda1

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_MKDOS to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_MKDOS when all shell commands have been configured.

PROGRAMMING INFORMATION:

The mkdos is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_mkdos(
    int    argc,
    char **argv
);

The configuration structure for the mkdos has the following prototype:

extern rtems_shell_cmd_t rtems_shell_MKDOS_Command;

4.2.19. mknod - make device special file¶

SYNOPSYS:

mknod [-rR] [-F fmt] [-g gid] [-m mode] [-u uid] name [c | b] [driver | major] minor
mknod [-rR] [-F fmt] [-g gid] [-m mode] [-u uid] name [c | b] major unit subunit
mknod [-rR] [-g gid] [-m mode] [-u uid] name [c | b] number
mknod [-rR] [-g gid] [-m mode] [-u uid] name p

DESCRIPTION:

The mknod command creates device special files, or fifos. Normally the shell script /dev/MAKEDEV is used to create special files for commonly known devices; it executes mknod with the appropriate arguments and can make all the files required for the device.

To make nodes manually, the arguments are:

-r

Replace an existing file if its type is incorrect.

-R

Replace an existing file if its type is incorrect. Correct the mode, user and group.

-g gid

Specify the group for the device node. The gid operand may be a numeric group ID or a group name. If a group name is also a numeric group ID, the operand is used as a group name. Precede a numeric group ID with a # to stop it being treated as a name.

-m mode

Specify the mode for the device node. The mode may be absolute or symbolic, see chmod.

-u uid

Specify the user for the device node. The uid operand may be a numeric user ID or a user name. If a user name is also a numeric user ID, the operand is used as a user name. Precede a numeric user ID with a # to stop it being treated as a name.

name

Device name, for example “tty” for a termios serial device or “hd” for a disk.

b | c | p

Type of device. If the device is a block type device such as a tape or disk drive which needs both cooked and raw special files, the type is b. All other devices are character type devices, such as terminal and pseudo devices, and are type c. Specifying p creates fifo files.

driver | major

The major device number is an integer number which tells the kernel which device driver entry point to use. If the device driver is configured into the current kernel it may be specified by driver name or major number.

minor

The minor device number tells the kernel which one of several similar devices the node corresponds to; for example, it may be a specific serial port or pty.

unit and subunit

The unit and subunit numbers select a subset of a device; for example, the unit may specify a particular disk, and the subunit a partition on that disk. (Currently this form of specification is only supported by the bsdos format, for compatibility with the BSD/OS mknod).

number

A single opaque device number. Useful for netbooted computers which require device numbers packed in a format that isn’t supported by -F.

EXIT STATUS:

The mknod utility exits 0 on success, and >0 if an error occurs.

NOTES:

None.

EXAMPLES:

SHLL [/] mknod c 3 0 /dev/ttyS10

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_MKNOD to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_MKNOD when all shell commands have been configured.

PROGRAMMING INFORMATION:

The mknod command is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_mknod(
    int    argc,
    char **argv
);

The configuration structure for the mknod has the following prototype:

extern rtems_shell_cmd_t rtems_shell_MKNOD_Command;

ORIGIN:

The implementation and portions of the documentation for this command are from NetBSD 4.0.

4.2.20. mkrfs - format RFS file system¶

SYNOPSYS:

mkrfs [-vsbiIo] device

DESCRIPTION:

Format the block device with the RTEMS File System (RFS). The default configuration with not parameters selects a suitable block size based on the size of the media being formatted.

The media is broken up into groups of blocks. The number of blocks in a group is based on the number of bits a block contains. The large a block the more blocks a group contains and the fewer groups in the file system.

The following options are provided:

-v

Display configuration and progress of the format.

-s

Set the block size in bytes.

-b

The number of blocks in a group. The block count must be equal or less than the number of bits in a block.

-i

Number of inodes in a group. The inode count must be equal or less than the number of bits in a block.

-I

Initialise the inodes. The default is not to initialise the inodes and to rely on the inode being initialised when allocated. Initialising the inode table helps recovery if a problem appears.

-o

Integer percentage of the media used by inodes. The default is 1%.

device

Path of the device to format.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

None.

EXAMPLES:

The following is an example of how to use mkrfs:

SHLL [/] $ mkrfs /dev/fdda

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_MKRFS to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_MKRFS when all shell commands have been configured.

PROGRAMMING INFORMATION:

The mkrfs command is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_mkrfs(
    int    argc,
    char **argv
);

The configuration structure for mkrfs has the following prototype:

extern rtems_shell_cmd_t rtems_shell_MKRFS_Command;

4.2.21. mount - mount disk¶

SYNOPSYS:

mount [-t fstype] [-r] [-L] device path

DESCRIPTION:

The mount command will mount a block device to a mount point using the specified file system. The files systems are:

• msdos - MSDOS File System

• tftp - TFTP Network File System

• ftp - FTP Network File System

• nfs - Network File System

• rfs - RTEMS File System

When the file system type is ‘msdos’ or ‘rfs’ the driver is a “block device driver” node present in the file system. The driver is ignored with the ‘tftp’ and ‘ftp’ file systems. For the ‘nfs’ file system the driver is the ‘host:/path’ string that described NFS host and the exported file system path.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

The mount point must exist.

The services offered by each file-system vary. For example you cannot list the directory of a TFTP file-system as this server is not provided in the TFTP protocol. You need to check each file-system’s documentation for the services provided.

EXAMPLES:

Mount the Flash Disk driver to the ‘/fd’ mount point:

SHLL [/] $ mount -t msdos /dev/flashdisk0 /fd

Mount the NFS file system exported path ‘bar’ by host ‘foo’:

$ mount -t nfs foo:/bar /nfs

Mount the TFTP file system on ‘/tftp’:

$ mount -t tftp /tftp

To access the TFTP files on server ‘10.10.10.10’: .. code-block:: shell

$ cat /tftp/10.10.10.10/test.txt

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_MOUNT to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_MOUNT when all shell commands have been configured.

The mount command includes references to file-system code. If you do not wish to include file-system that you do not use do not define the mount command support for that file-system. The file-system mount command defines are:

• msdos - CONFIGURE_SHELL_MOUNT_MSDOS

• tftp - CONFIGURE_SHELL_MOUNT_TFTP

• ftp - CONFIGURE_SHELL_MOUNT_FTP

• nfs - CONFIGURE_SHELL_MOUNT_NFS

• rfs - CONFIGURE_SHELL_MOUNT_RFS

An example configuration is:

#define CONFIGURE_SHELL_MOUNT_MSDOS
#ifdef RTEMS_NETWORKING
#define CONFIGURE_SHELL_MOUNT_TFTP
#define CONFIGURE_SHELL_MOUNT_FTP
#define CONFIGURE_SHELL_MOUNT_NFS
#define CONFIGURE_SHELL_MOUNT_RFS
#endif

PROGRAMMING INFORMATION:

The mount is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_mount(
    int    argc,
    char **argv
);

The configuration structure for the mount has the following prototype:

extern rtems_shell_cmd_t rtems_shell_MOUNT_Command;

4.2.22. mv - move files¶

SYNOPSYS:

mv [-fiv] source_file target_file
mv [-fiv] source_file... target_file

DESCRIPTION:

In its first form, the mv utility renames the file named by the source operand to the destination path named by the target operand. This form is assumed when the last operand does not name an already existing directory.

In its second form, mv moves each file named by a source operand to a destination file in the existing directory named by the directory operand. The destination path for each operand is the pathname produced by the concatenation of the last operand, a slash, and the final pathname component of the named file.

The following options are available:

-f

Do not prompt for confirmation before overwriting the destination path.

-i

Causes mv to write a prompt to standard error before moving a file that would overwrite an existing file. If the response from the standard input begins with the character ‘y’, the move is attempted.

-v

Cause mv to be verbose, showing files as they are processed.

The last of any -f or -i options is the one which affects mv’s behavior.

It is an error for any of the source operands to specify a nonexistent file or directory.

It is an error for the source operand to specify a directory if the target exists and is not a directory.

If the destination path does not have a mode which permits writing, mv prompts the user for confirmation as specified for the -i option.

Should the rename call fail because source and target are on different file systems, mv will remove the destination file, copy the source file to the destination, and then remove the source. The effect is roughly equivalent to:

rm -f destination_path && \
cp -PRp source_file destination_path && \
rm -rf source_file

EXIT STATUS:

The mv utility exits 0 on success, and >0 if an error occurs.

NOTES:

None.

EXAMPLES:

SHLL [/] mv /dev/console /dev/con1

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_MV to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_MV when all shell commands have been configured.

PROGRAMMING INFORMATION:

The mv command is implemented by a C language function which has the following prototype:

int rtems_shell_main_mv(
    int    argc,
    char **argv
);

The configuration structure for the mv has the following prototype:

extern rtems_shell_cmd_t rtems_shell_MV_Command;

ORIGIN:

The implementation and portions of the documentation for this command are from NetBSD 4.0.

4.2.23. pwd - print work directory¶

SYNOPSYS:

pwd

DESCRIPTION:

This command prints the fully qualified filename of the current working directory.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

None.

EXAMPLES:

The following is an example of how to use pwd:

SHLL [/] $ pwd
/
SHLL [/] $ cd dev
SHLL [/dev] $ pwd
/dev

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_PWD to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_PWD when all shell commands have been configured.

PROGRAMMING INFORMATION:

The pwd is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_pwd(
    int    argc,
    char argv
);

The configuration structure for the pwd has the following prototype:

extern rtems_shell_cmd_t rtems_shell_PWD_Command;

4.2.24. rmdir - remove empty directories¶

SYNOPSYS:

rmdir  [dir1 .. dirN]

DESCRIPTION:

This command removes the specified set of directories. If no directories are provided on the command line, no actions are taken.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

This command is a implemented using the rmdir(2) system call and all reasons that call may fail apply to this command.

EXAMPLES:

The following is an example of how to use rmdir:

SHLL [/] # mkdir joeldir
SHLL [/] # rmdir joeldir
SHLL [/] # ls joeldir
joeldir: No such file or directory.

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_RMDIR to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_RMDIR when all shell commands have been configured.

PROGRAMMING INFORMATION:

The rmdir is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_rmdir(
    int    argc,
    char **argv
);

The configuration structure for the rmdir has the following prototype:

extern rtems_shell_cmd_t rtems_shell_RMDIR_Command;

4.2.25. rm - remove files¶

SYNOPSYS:

rm file1 [file2 ... fileN]

DESCRIPTION:

This command deletes a name from the filesystem. If the specified file name was the last link to a file and there are no open file descriptor references to that file, then it is deleted and the associated space in the file system is made available for subsequent use.

If the filename specified was the last link to a file but there are open file descriptor references to it, then the file will remain in existence until the last file descriptor referencing it is closed.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

None.

EXAMPLES:

The following is an example of how to use rm:

SHLL [/] # cp /etc/passwd tmpfile
SHLL [/] # cat tmpfile
root:*:0:0:root::/:/bin/sh
rtems:*:1:1:RTEMS Application::/:/bin/sh
tty:!:2:2:tty owner::/:/bin/false
SHLL [/] # rm tmpfile
SHLL [/] # cat tmpfile
cat: tmpfile: No such file or directory

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_RM to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_RM when all shell commands have been configured.

PROGRAMMING INFORMATION:

The rm is implemented by a C language function which has the following prototype:

int rtems_shell_main_rm(
    int    argc,
    char **argv
);

The configuration structure for the rm has the following prototype: .. code-block:: c

extern rtems_shell_cmd_t rtems_shell_RM_Command;

4.2.26. umask - set file mode creation mask¶

SYNOPSYS:

umask [new_umask]

DESCRIPTION:

This command sets the user file creation mask to new_umask. The argument new_umask may be octal, hexadecimal, or decimal.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

This command does not currently support symbolic mode masks.

EXAMPLES:

The following is an example of how to use umask:

SHLL [/] $ umask
022
SHLL [/] $ umask 0666
0666
SHLL [/] $ umask
0666

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_UMASK to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_UMASK when all shell commands have been configured.

PROGRAMMING INFORMATION:

The umask is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_umask(
    int    argc,
    char **argv
);

The configuration structure for the umask has the following prototype:

extern rtems_shell_cmd_t rtems_shell_UMASK_Command;

4.2.27. unmount - unmount disk¶

SYNOPSYS:

unmount path

DESCRIPTION:

This command unmounts the device at the specified path.

EXIT STATUS:

This command returns 0 on success and non-zero if an error is encountered.

NOTES:

TBD - Surely there must be some warnings to go here.

EXAMPLES:

The following is an example of how to use unmount:

# unmount /mnt

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_UNMOUNT to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_UNMOUNT when all shell commands have been configured.

PROGRAMMING INFORMATION:

The unmount is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_unmount(
    int    argc,
    char **argv
);

The configuration structure for the unmount has the following prototype:

extern rtems_shell_cmd_t rtems_shell_UNMOUNT_Command;

5.2.1. mdump - display contents of memory¶

SYNOPSYS:

mdump [address [length [size]]]

DESCRIPTION:

This command displays the contents of memory at the address and length in size byte units specified on the command line.

When size is not provided, it defaults to 1 byte units. Values of 1, 2, and 4 are valid; all others will cause an error to be reported.

When length is not provided, it defaults to 320 which is twenty lines of output with sixteen bytes of output per line.

When address is not provided, it defaults to 0x00000000.

EXIT STATUS:

This command always returns 0 to indicate success.

NOTES:

Dumping memory from a non-existent address may result in an unrecoverable program fault.

EXAMPLES:

The following is an example of how to use mdump:

SHLL [/] $ mdump 0x10000 32
0x0001000000 00 00 00 00 00 00 00-00 00 00 00 00 00 00 00 ................
0x0001001000 00 00 00 00 00 00 00-00 00 00 00 00 00 00 00 ................
SHLL [/] $ mdump 0x02000000 32
0x02000000A1 48 00 00 29 00 80 33-81 C5 22 BC A6 10 21 00 .H..)..3.."...!.
0x02000010A1 48 00 00 29 00 80 33-81 C5 22 BC A6 10 21 01 .H..)..3.."...!.
SHLL [/] $ mdump 0x02001000 32
0x0200100003 00 80 00 82 10 60 00-81 98 40 00 83 48 00 00 ......`.....H..
0x0200101084 00 60 01 84 08 A0 07-86 10 20 01 87 28 C0 02 ..`....... ..(..

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_MDUMP to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_MDUMP when all shell commands have been configured.

PROGRAMMING INFORMATION:

The mdump is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_mdump(
    int    argc,
    char **argv
);

The configuration structure for the mdump has the following prototype:

extern rtems_shell_cmd_t rtems_shell_MDUMP_Command;

5.2.2. wdump - display contents of memory (word)¶

SYNOPSYS:

wdump [address [length]]

DESCRIPTION:

This command displays the contents of memory at the address and length in bytes specified on the command line.

This command is equivalent to mdump address length 2.

When length is not provided, it defaults to 320 which is twenty lines of output with eight words of output per line.

When address is not provided, it defaults to 0x00000000.

EXIT STATUS:

This command always returns 0 to indicate success.

NOTES:

Dumping memory from a non-existent address may result in an unrecoverable program fault.

EXAMPLES:

The following is an example of how to use wdump:

SHLL [/] $ wdump 0x02010000 32
0x02010000 0201 08D8 0201 08C0-0201 08AC 0201 0874 ...............t
0x02010010 0201 0894 0201 0718-0201 0640 0201 0798 ...............

CONFIGURATION:

This command is included in the default shell command set. When building a custom command set, define CONFIGURE_SHELL_COMMAND_WDUMP to have this command included.

This command can be excluded from the shell command set by defining CONFIGURE_SHELL_NO_COMMAND_WDUMP when all shell commands have been configured.

PROGRAMMING INFORMATION:

The wdump is implemented by a C language function which has the following prototype:

int rtems_shell_rtems_main_wdump(
    int    argc,
    char **argv
);

The configuration structure for the wdump has the following prototype:

extern rtems_shell_cmd_t rtems_shell_WDUMP_Command;

5.2.3. ldump - display contents of memory (longword)¶

SYNOPSYS:

ldump [address [length]]

DESCRIPTION:

This command displays the contents of memory at the address and length in bytes specified on the command line.

This command is equivalent to mdump address length 4.

When length is not provided, it defaults to 320 which is twenty lines of output with four longwords of output per line.

When address is not provided, it defaults to 0x00000000.

EXIT STATUS:

This command always returns 0 to indicate success.

NOTES:

Dumping memory from a non-existent address may result in an unrecoverable program fault.

EXAMPLES:

The following is an example of how to use ldump:

SHLL [/] $ ldump 0x02010000 32
0x02010000 020108D8 020108C0-020108AC 02010874 ...............t
0x02010010 020 0894 02010718-02010640 02010798 ...............