Linux and UNIX Man Pages

Linux & Unix Commands - Search Man Pages

atexit(3) [hpux man page]

atexit(3)						     Library Functions Manual							 atexit(3)

atexit - register a function to be called at program termination SYNOPSIS
registers the function func to be called, without arguments, at normal program termination. Functions registered by are called in reverse order of registration. An call during exit processing is always unsuccessful. The number of registered functions should not exceed as specified in When necessary, or (see crt0(3) and for PA-RISC systems or for Itanium-based systems) registers one or more functions with to allow some processing at normal program termination. This registration occurs before any other. RETURN VALUE
returns zero if the registration is successful; non-zero if unsuccessful. SEE ALSO
exit(2), crt0(3), for PA-RISC systems. for Itanium-based systems. STANDARDS CONFORMANCE

Check Out this Related Man Page

ATEXIT(3)						     Linux Programmer's Manual							 ATEXIT(3)

atexit - register a function to be called at normal process termination SYNOPSIS
#include <stdlib.h> int atexit(void (*function)(void)); DESCRIPTION
The atexit() function registers the given function to be called at normal process termination, either via exit(3) or via return from the program's main(). Functions so registered are called in the reverse order of their registration; no arguments are passed. The same function may be registered multiple times: it is called once for each registration. POSIX.1-2001 requires that an implementation allow at least ATEXIT_MAX (32) such functions to be registered. The actual limit supported by an implementation can be obtained using sysconf(3). When a child process is created via fork(2), it inherits copies of its parent's registrations. Upon a successful call to one of the exec(3) functions, all registrations are removed. RETURN VALUE
The atexit() function returns the value 0 if successful; otherwise it returns a nonzero value. CONFORMING TO
SVr4, 4.3BSD, C89, C99, POSIX.1-2001. NOTES
Functions registered using atexit() (and on_exit(3)) are not called if a process terminates abnormally because of the delivery of a signal. If one of the functions registered functions calls _exit(2), then any remaining functions are not invoked, and the other process termina- tion steps performed by exit(3) are not performed. POSIX.1-2001 says that the result of calling exit(3) more than once (i.e., calling exit(3) within a function registered using atexit(3)) is undefined. On some systems (but not Linux), this can result in an infinite recursion; portable programs should not invoke exit(3) inside a function registered using atexit(3). The atexit() and on_exit(3) functions register functions on the same list: at normal process termination, the registered functions are invoked in reverse order of their registration by these two functions. POSIX.1-2001 says that the result is undefined if longjmp(3) is used to terminate execution of one of the functions registered atexit(). Linux Notes Since glibc 2.2.3, atexit() (and on_exit(3)) can be used within a shared library to establish functions that are called when the shared library is unloaded. EXAMPLE
#include <stdio.h> #include <stdlib.h> #include <unistd.h> void bye(void) { printf("That was all, folks "); } int main(void) { long a; int i; a = sysconf(_SC_ATEXIT_MAX); printf("ATEXIT_MAX = %ld ", a); i = atexit(bye); if (i != 0) { fprintf(stderr, "cannot set exit function "); exit(EXIT_FAILURE); } exit(EXIT_SUCCESS); } SEE ALSO
_exit(2), exit(3), on_exit(3) COLOPHON
This page is part of release 3.25 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at Linux 2008-12-05 ATEXIT(3)
Man Page

Featured Tech Videos