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## 2 Standard Utility Functions (`stdlib.h`)

This chapter groups utility functions useful in a variety of programs. The corresponding declarations are in the header file `stdlib.h`.

- _Exit: End program execution without cleaning up
- a64l: String to long long
- 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
- atoll: String to long long
- 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
- gcvt: Format double or float as string
- exit: End program execution
- getenv: Look up environment variable
- itoa: Integer to string
- labs: Long integer absolute value (magnitude)
- ldiv: Divide two long integers
- llabs: Long long integer absolute value (magnitude)
- lldiv: Divide two long long integers
- malloc: Allocate and manage memory (malloc, realloc, free)
- mallinfo: Get information about allocated memory
- __malloc_lock: Lock memory pool for malloc and free
- mbsrtowcs: Convert a character string to a wide-character string
- mbstowcs: Minimal multibyte string to wide string converter
- mblen: Minimal multibyte length
- mbtowc: Minimal multibyte to wide character converter
- on_exit: Request execution of functions at program exit
- qsort: Array sort
- rand: Pseudo-random numbers
- random: Pseudo-random numbers
- rand48: Uniformly distributed pseudo-random numbers
- rpmatch: Determine whether response is affirmative or negative
- strtod: String to double or float
- strtol: String to long
- strtoll: String to long long
- strtoul: String to unsigned long
- strtoull: String to unsigned long long
- wcsrtombs: Convert a wide-character string to a character string
- wcstod: Wide string to double or float
- wcstol: Wide string to long
- wcstoll: Wide string to long long
- wcstoul: Wide string to unsigned long
- wcstoull: Wide string to unsigned long long
- system: Execute command string
- utoa: Unsigned integer to string
- wcstombs: Minimal wide string to multibyte string converter
- wctomb: Minimal wide character to multibyte converter