exit(3) - NetBSD Manual Pages

EXIT(3)                 NetBSD Library Functions Manual                EXIT(3)


NAME

     exit -- perform normal program termination


LIBRARY

     Standard C Library (libc, -lc)


SYNOPSIS

     #include <stdlib.h>

     void
     exit(int status);


DESCRIPTION

     exit() terminates a process.  The status values EXIT_SUCCESS and
     EXIT_FAILURE can be used to indicate successful and unsuccessful termina-
     tion, respectively.

     Before termination it performs the following functions in the order
     listed:

           1.   Call the functions registered with the atexit(3) function, in
                the reverse order of their registration.

           2.   Flush all open output streams.

           3.   Close all open streams.

           4.   Unlink all files created with the tmpfile(3) function.

     Following this, exit() calls _exit(2).


RESTRICTIONS

     Standard C guarantees only that the values zero, EXIT_SUCCESS, and
     EXIT_FAILURE produce meaningful results.  POSIX extends this to guarantee
     that the least significant 8 bits of status are preserved and returned to
     the parent via wait(2).  Values outside the supported range 0-255 are
     bitwise-truncated; therefore, negative values should not be used.


RETURN VALUES

     The exit() function never returns.


SEE ALSO

     _exit(2), at_quick_exit(3), atexit(3), intro(3), quick_exit(3),
     tmpfile(3)


STANDARDS

     The exit() function conforms to ANSI X3.159-1989 (``ANSI C89'').


HISTORY

     The exit() function appeared in Version 1 AT&T UNIX.

NetBSD 9.0                     September 1, 2019                    NetBSD 9.0