dwww Home | Manual pages | Find package

on_exit(3)                 Library Functions Manual                 on_exit(3)

NAME
       on_exit  -  register a function to be called at normal process termina-
       tion

LIBRARY
       Standard C library (libc, -lc)

SYNOPSIS
       #include <stdlib.h>

       int on_exit(void (*function)(int, void *), void *arg);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       on_exit():
           Since glibc 2.19:
               _DEFAULT_SOURCE
           glibc 2.19 and earlier:
               _BSD_SOURCE || _SVID_SOURCE

DESCRIPTION
       The on_exit() function registers the given function  to  be  called  at
       normal  process termination, whether via exit(3) or via return from the
       program's main().  The function is passed the status argument given  to
       the last call to exit(3) and the arg argument from on_exit().

       The  same  function may be registered multiple times: it is called once
       for each registration.

       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 on_exit() function returns the value 0 if successful; otherwise  it
       returns a nonzero value.

ATTRIBUTES
       For  an  explanation  of  the  terms  used  in  this  section,  see at-
       tributes(7).

       ┌────────────────────────────────────────────┬───────────────┬─────────┐
       │InterfaceAttributeValue   │
       ├────────────────────────────────────────────┼───────────────┼─────────┤
       │on_exit()                                   │ Thread safety │ MT-Safe │
       └────────────────────────────────────────────┴───────────────┴─────────┘

STANDARDS
       This function comes from SunOS 4, but is also present in glibc.  It  no
       longer  occurs in Solaris (SunOS 5).  Portable application should avoid
       this function, and use the standard atexit(3) instead.

NOTES
       By the time function is executed, stack (auto)  variables  may  already
       have  gone  out  of scope.  Therefore, arg should not be a pointer to a
       stack variable; it may however be a pointer to a  heap  variable  or  a
       global variable.

SEE ALSO
       _exit(2), atexit(3), exit(3)

Linux man-pages 6.03              2023-02-05                        on_exit(3)

Generated by dwww version 1.15 on Wed Jun 26 18:07:35 CEST 2024.