atexit(3c) [opensolaris man page]

atexit(3C)						   Standard C Library Functions 						atexit(3C)

NAME

       atexit - register a function to run at process termination or object unloading

SYNOPSIS

       #include <stdlib.h>

       int atexit(void (*func)(void));

DESCRIPTION

       The atexit() function registers the function pointed to by func to be called without arguments on normal termination of the program or when
       the object defining the function is unloaded.

       Normal termination occurs by either a call to the exit(3C) function or a return from  main().  Object  unloading  occurs  when  a  call	to
       dlclose(3C) results in the object becoming unreferenced.

       The  number  of functions that may be registered with atexit() is limited only by available memory (refer to the _SC_ATEXIT_MAX argument of
       sysconf(3C)).

       After a successful call to any of the exec(2) functions, any functions previously registered by atexit() are no longer registered.

       On process exit, functions are called in the reverse order of their registration. On  object  unloading,  any  functions  belonging  to	an
       unloadable object are called in the reverse order of their registration.

RETURN VALUES

       Upon successful completion, the atexit() function returns 0. Otherwise, it returns a non-zero value.

ERRORS

       The atexit() function may fail if:

       ENOMEM	 Insufficient storage space is available.

USAGE

       The functions registered by a call to atexit() must return to ensure that all registered functions are called.

       There is no way for an application to tell how many functions have already been registered with atexit().

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Standard			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       exec(2), dlclose(3C), exit(3C), sysconf(3C), attributes(5)

SunOS 5.11							    25 May 2001 							atexit(3C)

ATEXIT(3P)						     POSIX Programmer's Manual							ATEXIT(3P)

PROLOG

       This  manual page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (consult the correspond-
       ing Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

NAME

       atexit - register a function to run at process termination

SYNOPSIS

       #include <stdlib.h>

       int atexit(void (*func)(void));

DESCRIPTION

       The atexit() function shall register the function pointed to by func, to be called without arguments at normal program termination. At nor-
       mal  program  termination,  all	functions registered by the atexit() function shall be called, in the reverse order of their registration,
       except that a function is called after any previously registered functions that had already been called at the time it was registered. Nor-
       mal termination occurs either by a call to exit() or a return from main().

       At least 32 functions can be registered with atexit().

       After a successful call to any of the exec functions, any functions previously registered by atexit() shall no longer be registered.

RETURN VALUE

       Upon successful completion, atexit() shall return 0; otherwise, it shall return a non-zero value.

ERRORS

       No errors are defined.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       The functions registered by a call to atexit() must return to ensure that all registered functions are called.

       The  application should call sysconf() to obtain the value of {ATEXIT_MAX}, the number of functions that can be registered. There is no way
       for an application to tell how many functions have already been registered with atexit().

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       exit(), sysconf(), the Base Definitions volume of IEEE Std 1003.1-2001, <stdlib.h>

COPYRIGHT

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technol-
       ogy -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
       Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and  the  original  IEEE
       and  The  Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained
       online at http://www.opengroup.org/unix/online.html .

IEEE
/The Open Group						       2003								ATEXIT(3P)