LDP: Update original to LDP v3.76

[linuxjm/LDP_man-pages.git] / original / man3 / memcmp.3

diff --git a/original/man3/memcmp.3 b/original/man3/memcmp.3
index 37842ae..1955cca 100644 (file)
--- a/original/man3/memcmp.3
+++ b/original/man3/memcmp.3
@@ -27,7 +27,7 @@
 .\"     Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
 .\"     386BSD man pages
 .\" Modified Sat Jul 24 18:55:27 1993 by Rik Faith (faith@cs.unc.edu)
-.TH MEMCMP 3  2014-03-14 "" "Linux Programmer's Manual"
+.TH MEMCMP 3  2014-12-31 "" "Linux Programmer's Manual"
 .SH NAME
 memcmp \- compare memory areas
 .SH SYNOPSIS
@@ -57,6 +57,10 @@ that differ in
 .I s1
 and
 .IR s2 .
+
+If
+.I n
+is zero, the return value is zero.
 .SH ATTRIBUTES
 .SS Multithreading (see pthreads(7))
 The
@@ -64,6 +68,12 @@ The
 function is thread-safe.
 .SH CONFORMING TO
 SVr4, 4.3BSD, C89, C99, POSIX.1-2001.
+.SH NOTES
+.PP
+Do not use
+.BR memcmp ()
+to compare security critical data, such as cryptographic secrets,
+because the required CPU time depends on the amount of equal bytes.
 .SH SEE ALSO
 .BR bcmp (3),
 .BR strcasecmp (3),
@@ -73,7 +83,7 @@ SVr4, 4.3BSD, C89, C99, POSIX.1-2001.
 .BR strncmp (3),
 .BR wmemcmp (3)
 .SH COLOPHON
-This page is part of release 3.75 of the Linux
+This page is part of release 3.76 of the Linux
 .I man-pages
 project.
 A description of the project,