21. Services Provided by C Library (libc)

21.1. Introduction

This section lists the routines that provided by the Newlib C Library.

21.2. Standard Utility Functions (stdlib.h)

  • abort - Abnormal termination of a program

  • abs - Integer absolute value (magnitude)

  • assert - Macro for Debugging Diagnostics

  • atexit - Request execution of functions at program exit

  • atof - String to double or float

  • atoi - String to integer

  • bsearch - Binary search

  • calloc - Allocate space for arrays

  • div - Divide two integers

  • ecvtbuf - Double or float to string of digits

  • ecvt - Double or float to string of digits (malloc result)

  • __env_lock - Lock environment list for getenv and setenv

  • gvcvt - Format double or float as string

  • exit - End program execution

  • getenv - Look up environment variable

  • labs - Long integer absolute value (magnitude)

  • ldiv - Divide two long integers

  • malloc - Allocate memory

  • realloc - Reallocate memory

  • free - Free previously allocated memory

  • mallinfo - Get information about allocated memory

  • __malloc_lock - Lock memory pool for malloc and free

  • mbstowcs - Minimal multibyte string to wide string converter

  • mblen - Minimal multibyte length

  • mbtowc - Minimal multibyte to wide character converter

  • qsort - Sort an array

  • rand - Pseudo-random numbers

  • strtod - String to double or float

  • strtol - String to long

  • strtoul - String to unsigned long

  • system - Execute command string

  • wcstombs - Minimal wide string to multibyte string converter

  • wctomb - Minimal wide character to multibyte converter

21.3. Character Type Macros and Functions (ctype.h)

  • isalnum - Alphanumeric character predicate

  • isalpha - Alphabetic character predicate

  • isascii - ASCII character predicate

  • iscntrl - Control character predicate

  • isdigit - Decimal digit predicate

  • islower - Lower-case character predicate

  • isprint - Printable character predicates (isprint, isgraph)

  • ispunct - Punctuation character predicate

  • isspace - Whitespace character predicate

  • isupper - Uppercase character predicate

  • isxdigit - Hexadecimal digit predicate

  • toascii - Force integers to ASCII range

  • tolower - Translate characters to lower case

  • toupper - Translate characters to upper case

21.4. Input and Output (stdio.h)

  • clearerr - Clear file or stream error indicator

  • fclose - Close a file

  • feof - Test for end of file

  • ferror - Test whether read/write error has occurred

  • fflush - Flush buffered file output

  • fgetc - Get a character from a file or stream

  • fgetpos - Record position in a stream or file

  • fgets - Get character string from a file or stream

  • fiprintf - Write formatted output to file (integer only)

  • fopen - Open a file

  • fdopen - Turn an open file into a stream

  • fputc - Write a character on a stream or file

  • fputs - Write a character string in a file or stream

  • fread - Read array elements from a file

  • freopen - Open a file using an existing file descriptor

  • fseek - Set file position

  • fsetpos - Restore position of a stream or file

  • ftell - Return position in a stream or file

  • fwrite - Write array elements from memory to a file or stream

  • getc - Get a character from a file or stream (macro)

  • getchar - Get a character from standard input (macro)

  • gets - Get character string from standard input (obsolete)

  • iprintf - Write formatted output (integer only)

  • mktemp - Generate unused file name

  • perror - Print an error message on standard error

  • putc - Write a character on a stream or file (macro)

  • putchar - Write a character on standard output (macro)

  • puts - Write a character string on standard output

  • remove - Delete a file’s name

  • rename - Rename a file

  • rewind - Reinitialize a file or stream

  • setbuf - Specify full buffering for a file or stream

  • setvbuf - Specify buffering for a file or stream

  • siprintf - Write formatted output (integer only)

  • printf - Write formatted output

  • scanf - Scan and format input

  • tmpfile - Create a temporary file

  • tmpnam - Generate name for a temporary file

  • vprintf - Format variable argument list

21.5. Strings and Memory (string.h)

  • bcmp - Compare two memory areas

  • bcopy - Copy memory regions

  • bzero - Initialize memory to zero

  • index - Search for character in string

  • memchr - Find character in memory

  • memcmp - Compare two memory areas

  • memcpy - Copy memory regions

  • memmove - Move possibly overlapping memory

  • memset - Set an area of memory

  • rindex - Reverse search for character in string

  • strcasecmp - Compare strings ignoring case

  • strcat - Concatenate strings

  • strchr - Search for character in string

  • strcmp - Character string compare

  • strcoll - Locale specific character string compare

  • strcpy - Copy string

  • strcspn - Count chars not in string

  • strerror - Convert error number to string

  • strlen - Character string length

  • strlwr - Convert string to lower case

  • strncasecmp - Compare strings ignoring case

  • strncat - Concatenate strings

  • strncmp - Character string compare

  • strncpy - Counted copy string

  • strpbrk - Find chars in string

  • strrchr - Reverse search for character in string

  • strspn - Find initial match

  • strstr - Find string segment

  • strtok - Get next token from a string

  • strupr - Convert string to upper case

  • strxfrm - Transform string

21.6. Signal Handling (signal.h)

  • raise - Send a signal

  • signal - Specify handler subroutine for a signal

21.7. Time Functions (time.h)

  • asctime - Format time as string

  • clock - Cumulative processor time

  • ctime - Convert time to local and format as string

  • difftime - Subtract two times

  • gmtime - Convert time to UTC (GMT) traditional representation

  • localtime - Convert time to local representation

  • mktime - Convert time to arithmetic representation

  • strftime - Flexible calendar time formatter

  • time - Get current calendar time (as single number)

21.8. Locale (locale.h)

  • setlocale - Select or query locale

21.9. Reentrant Versions of Functions

  • Equivalent for errno variable: - errno_r - XXX

  • Locale functions:

    • localeconv_r - XXX

    • setlocale_r - XXX

  • Equivalents for stdio variables:

    • stdin_r - XXX

    • stdout_r - XXX

    • stderr_r - XXX

  • Stdio functions:

    • fdopen_r - XXX

    • perror_r - XXX

    • tempnam_r - XXX

    • fopen_r - XXX

    • putchar_r - XXX

    • tmpnam_r - XXX

    • getchar_r - XXX

    • puts_r - XXX

    • tmpfile_r - XXX

    • gets_r - XXX

    • remove_r - XXX

    • vfprintf_r - XXX

    • iprintf_r - XXX

    • rename_r - XXX

    • vsnprintf_r - XXX

    • mkstemp_r - XXX

    • snprintf_r - XXX

    • vsprintf_r - XXX

    • mktemp_t - XXX

    • sprintf_r - XXX

  • Signal functions:

    • init_signal_r - XXX

    • signal_r - XXX

    • kill_r - XXX

    • _sigtramp_r - XXX

    • raise_r - XXX

  • Stdlib functions:

    • calloc_r - XXX

    • mblen_r - XXX

    • srand_r - XXX

    • dtoa_r - XXX

    • mbstowcs_r - XXX

    • strtod_r - XXX

    • free_r - XXX

    • mbtowc_r - XXX

    • strtol_r - XXX

    • getenv_r - XXX

    • memalign_r - XXX

    • strtoul_r - XXX

    • mallinfo_r - XXX

    • mstats_r - XXX

    • system_r - XXX

    • malloc_r - XXX

    • rand_r - XXX

    • wcstombs_r - XXX

    • malloc_r - XXX

    • realloc_r - XXX

    • wctomb_r - XXX

    • malloc_stats_r - XXX

    • setenv_r - XXX

  • String functions:

    • strtok_r - XXX

  • System functions:

    • close_r - XXX

    • link_r - XXX

    • unlink_r - XXX

    • execve_r - XXX

    • lseek_r - XXX

    • wait_r - XXX

    • fcntl_r - XXX

    • open_r - XXX

    • write_r - XXX

    • fork_r - XXX

    • read_r - XXX

    • fstat_r - XXX

    • sbrk_r - XXX

    • gettimeofday_r - XXX

    • stat_r - XXX

    • getpid_r - XXX

    • times_r - XXX

  • Time function:

    • asctime_r - XXX

21.10. Miscellaneous Macros and Functions

  • unctrl - Return printable representation of a character

21.11. Variable Argument Lists

  • Stdarg (stdarg.h):

    • va_start - XXX

    • va_arg - XXX

    • va_end - XXX

  • Vararg (varargs.h):

    • va_alist - XXX

    • va_start-trad - XXX

    • va_arg-trad - XXX

    • va_end-trad - XXX

21.12. Reentrant System Calls

  • open_r - XXX

  • close_r - XXX

  • lseek_r - XXX

  • read_r - XXX

  • write_r - XXX

  • fork_r - XXX

  • wait_r - XXX

  • stat_r - XXX

  • fstat_r - XXX

  • link_r - XXX

  • unlink_r - XXX

  • sbrk_r - XXX