File and Directory Commands mknod - make device special file
RTEMS Shell User's Guide
3.2.10: 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:
RTEMS Shell User's Guide