man3/abort.3

   1 .\" Copyright 2007 (C) Michael Kerrisk <mtk.manpages@gmail.com>
   2 .\" some parts Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
   3 .\"
   4 .\" SPDX-License-Identifier: Linux-man-pages-copyleft
   5 .\"
   6 .\" References consulted:
   7 .\"     Linux libc source code
   8 .\"     Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
   9 .\"     386BSD man pages
  10 .\" Modified Sat Jul 24 21:46:21 1993 by Rik Faith (faith@cs.unc.edu)
  11 .\" Modified Fri Aug  4 10:51:53 2000 - patch from Joseph S. Myers
  12 .\" 2007-12-15, mtk, Mostly rewritten
  13 .\"
  14 .TH ABORT 3 (date) "Linux man-pages (unreleased)"
  15 .SH NAME
  16 abort \- cause abnormal process termination
  17 .SH LIBRARY
  18 Standard C library
  19 .RI ( libc ", " \-lc )
  20 .SH SYNOPSIS
  21 .nf
  22 .B #include <stdlib.h>
  23 .PP
  24 .B noreturn void abort(void);
  25 .fi
  26 .SH DESCRIPTION
  27 The
  28 .BR abort ()
  29 function first unblocks the
  30 .B SIGABRT
  31 signal, and then raises that signal for the calling process
  32 (as though
  33 .BR raise (3)
  34 was called).
  35 This results in the abnormal termination of the process unless the
  36 .B SIGABRT
  37 signal is caught and the signal handler does not return
  38 (see
  39 .BR longjmp (3)).
  40 .PP
  41 If the
  42 .B SIGABRT
  43 signal is ignored, or caught by a handler that returns, the
  44 .BR abort ()
  45 function will still terminate the process.
  46 It does this by restoring the default disposition for
  47 .B SIGABRT
  48 and then raising the signal for a second time.
  49 .SH RETURN VALUE
  50 The
  51 .BR abort ()
  52 function never returns.
  53 .SH ATTRIBUTES
  54 For an explanation of the terms used in this section, see
  55 .BR attributes (7).
  56 .ad l
  57 .nh
  58 .TS
  59 allbox;
  60 lbx lb lb
  61 l l l.
  62 Interface       Attribute       Value
  63 T{
  64 .BR abort ()
  65 T}      Thread safety   MT-Safe
  66 .TE
  67 .hy
  68 .ad
  69 .sp 1
  70 .SH STANDARDS
  71 SVr4, POSIX.1-2001, POSIX.1-2008, 4.3BSD, C89, C99.
  72 .SH NOTES
  73 Up until glibc 2.26,
  74 if the
  75 .BR abort ()
  76 function caused process termination,
  77 all open streams were closed and flushed (as with
  78 .BR fclose (3)).
  79 However, in some cases this could result in deadlocks and data corruption.
  80 Therefore, starting with glibc 2.27,
  81 .\" glibc commit 91e7cf982d0104f0e71770f5ae8e3faf352dea9f
  82 .BR abort ()
  83 terminates the process without flushing streams.
  84 POSIX.1 permits either possible behavior, saying that
  85 .BR abort ()
  86 "may include an attempt to effect fclose() on all open streams".
  87 .SH SEE ALSO
  88 .BR gdb (1),
  89 .BR sigaction (2),
  90 .BR assert (3),
  91 .BR exit (3),
  92 .BR longjmp (3),
  93 .BR raise (3)