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