err.3: EXAMPLES: use EXIT_FAILURE rather than 1 as exit status

[thirdparty/man-pages.git] / man3 / assert.3

diff --git a/man3/assert.3 b/man3/assert.3
index ecd168d429edd42fb2e5344088f9205a1aaf5e38..b5c0e7831ab534a24146dab7e50b0e2575ebbee4 100644 (file)
--- a/man3/assert.3
+++ b/man3/assert.3
@@ -1,5 +1,6 @@
-.\" (c) 1993 by Thomas Koenig (ig25@rz.uni-karlsruhe.de)
+.\" Copyright (c) 1993 by Thomas Koenig (ig25@rz.uni-karlsruhe.de)
 .\"
+.\" %%%LICENSE_START(VERBATIM)
 .\" Permission is granted to make and distribute verbatim copies of this
 .\" manual provided the copyright notice and this permission notice are
 .\" preserved on all copies.
@@ -19,43 +20,69 @@
 .\"
 .\" Formatted or processed versions of this manual, if unaccompanied by
 .\" the source, must acknowledge the copyright and authors of this work.
-.\" License.
+.\" %%%LICENSE_END
+.\"
 .\" Modified Sat Jul 24 21:42:42 1993 by Rik Faith <faith@cs.unc.edu>
 .\" Modified Tue Oct 22 23:44:11 1996 by Eric S. Raymond <esr@thyrsus.com>
-.TH ASSERT 3  2002-08-25 "C99" "Linux Programmer's Manual"
+.\" Modified Thu Jun  2 23:44:11 2016 by Nikos Mavrogiannopoulos <nmav@redhat.com>
+.TH ASSERT 3  2017-09-15 "GNU" "Linux Programmer's Manual"
 .SH NAME
 assert \- abort the program if assertion is false
 .SH SYNOPSIS
 .nf
 .B #include <assert.h>
-.sp
+.PP
 .BI "void assert(scalar " expression );
 .fi
 .SH DESCRIPTION
+This macro can help programmers find bugs in their programs,
+or handle exceptional cases
+via a crash that will produce limited debugging output.
+.PP
+If
+.I expression
+is false (i.e., compares equal to zero),
+.BR assert ()
+prints an error message to standard error
+and terminates the program by calling
+.BR abort (3).
+The error message includes the name of the file and function containing the
+.BR assert ()
+call, the source code line number of the call, and the text of the argument;
+something like:
+.PP
+    prog: some_file.c:16: some_func: Assertion `val == 0' failed.
+.PP
 If the macro
 .B NDEBUG
-was defined at the moment
+is defined at the moment
 .I <assert.h>
 was last included, the macro
 .BR assert ()
 generates no code, and hence does nothing at all.
-Otherwise, the macro
+It is not recommended to define
+.B NDEBUG
+if using
 .BR assert ()
-prints an error message to standard error and terminates the program
-by calling
-.BR abort ()
-if
-.I expression
-is false (i.e., compares equal to zero).
-.LP
-The purpose of this macro is to help the programmer find bugs in
-his program.
-The message "assertion failed in file foo.c, function
-do_bar(), line 1287" is of no help at all to a user.
-.SH "RETURN VALUE"
+to detect error conditions since the software
+may behave non-deterministically.
+.SH RETURN VALUE
 No value is returned.
-.SH "CONFORMING TO"
-POSIX.1-2001, C89, C99.
+.SH ATTRIBUTES
+For an explanation of the terms used in this section, see
+.BR attributes (7).
+.TS
+allbox;
+lb lb lb
+l l l.
+Interface      Attribute       Value
+T{
+.BR assert ()
+T}     Thread safety   MT-Safe
+.TE
+.sp 1
+.SH CONFORMING TO
+POSIX.1-2001, POSIX.1-2008, C89, C99.
 In C89,
 .I expression
 is required to be of type
@@ -66,12 +93,12 @@ it may have any scalar type.
 .SH BUGS
 .BR assert ()
 is implemented as a macro; if the expression tested has side-effects,
-program behaviour will be different depending on whether
+program behavior will be different depending on whether
 .B NDEBUG
 is defined.
 This may create Heisenbugs which go away when debugging
 is turned on.
-.SH "SEE ALSO"
+.SH SEE ALSO
 .BR abort (3),
 .BR assert_perror (3),
 .BR exit (3)