SYNOPSIS

     #include <stdlib.h>

     int
     atexit(void (*function)(void));

DESCRIPTION

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

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

     At least 32 functions can always be registered, and 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 functions is unmodified.

SEE ALSO

     exit(3)

STANDARDS

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

BSD                            September 6, 2002                           BSD