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ATEXIT(3)                BSD Library Functions Manual                ATEXIT(3)

NAME
     atexit -- register a function to be called on exit

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <stdlib.h>

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

DESCRIPTION
     The atexit() function registers the function func to be called at program exit, whether via exit(3) or
     via return from the program's main().  Functions so registered are called in reverse order; no argu-ments arguments
     ments are passed.

     These functions must not call exit(); if it should be necessary to terminate the process while in such
     a function, the _exit(2) function should be used.  (Alternatively, the function may cause abnormal
     process termination, for example by calling abort(3).)

     At least 32 functions can always be registered; more are allowed as long as sufficient memory can be
     allocated.

RETURN VALUES
     The atexit() function returns the value 0 if successful; otherwise the value -1 is returned and the
     global variable errno is set to indicate the error.

ERRORS
     [ENOMEM]           No memory was available to add the function to the list.  The existing list of func-tions functions
                        tions is unmodified.

SEE ALSO
     exit(3)

STANDARDS
     The atexit() function conforms to ISO/IEC 9899:1990 (``ISO C90'').

BSD                            September 6, 2002                           BSD