NAME

       abort - generate an abnormal process abort

SYNOPSIS

       #include <stdlib.h>

       void abort(void);

DESCRIPTION

       The  abort() function shall cause abnormal process termination to occur, unless the signal
       SIGABRT is being caught and the signal handler does not return.

       The abnormal termination processing shall include the default actions defined for  SIGABRT
       and may include an attempt to effect fclose() on all open streams.

       The SIGABRT signal shall be sent to the calling process as if by means of raise() with the
       argument SIGABRT.

       The status made available to wait() or waitpid() by abort() shall be  that  of  a  process
       terminated  by  the  SIGABRT  signal.   The  abort()  function  shall override blocking or
       ignoring the SIGABRT signal.

RETURN VALUE

       The abort() function shall not return.

ERRORS

       No errors are defined.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       Catching the signal is intended to provide the application writer with a portable means to
       abort   processing,  free  from  possible  interference  from  any  implementation-defined
       functions.

RATIONALE

       The ISO/IEC 9899:1999 standard requires the  abort()  function  to  be  async-signal-safe.
       Since  IEEE Std 1003.1-2001  defers  to  the ISO C standard, this required a change to the
       DESCRIPTION from ``shall include the effect of fclose()'' to ``may include an  attempt  to
       effect fclose().''

       The  revised  wording permits some backwards-compatibility and avoids a potential deadlock
       situation.

       The Open Group Base Resolution bwg2002-003 is applied, removing the following  XSI  shaded
       paragraph from the DESCRIPTION:

       ``On XSI-conformant systems, in addition the abnormal termination processing shall include
       the effect of fclose() on message catalog descriptors.''

       There were several reasons to remove this paragraph:

        * No special processing of open message catalogs needs to be performed prior to  abnormal
          process termination.

        * The main reason to specifically mention that abort() includes the effect of fclose() on
          open streams is to flush output queued on the stream. Message catalogs in this  context
          are read-only and, therefore, do not need to be flushed.

        * The effect of fclose() on a message catalog descriptor is unspecified.  Message catalog
          descriptors are allowed, but not required to be implemented using  a  file  descriptor,
          but there is no mention in IEEE Std 1003.1-2001 of a message catalog descriptor using a
          standard I/O stream FILE object as would be expected by fclose().

FUTURE DIRECTIONS

       None.

SEE ALSO

       exit() , kill() , raise() , signal() , wait() , waitpid() , 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 Technology  --  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 .