man3/strcmp.3

   1 .\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
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  25 .\" References consulted:
  26 .\"     Linux libc source code
  27 .\"     Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
  28 .\"     386BSD man pages
  29 .\" Modified Sat Jul 24 18:08:52 1993 by Rik Faith (faith@cs.unc.edu)
  30 .\" Modified 2001-08-31, aeb
  31 .\"
  32 .TH STRCMP 3  2015-08-08 "" "Linux Programmer's Manual"
  33 .SH NAME
  34 strcmp, strncmp \- compare two strings
  35 .SH SYNOPSIS
  36 .nf
  37 .B #include <string.h>
  38 .PP
  39 .BI "int strcmp(const char *" s1 ", const char *" s2 );
  40 .PP
  41 .BI "int strncmp(const char *" s1 ", const char *" s2 ", size_t " n );
  42 .fi
  43 .SH DESCRIPTION
  44 The
  45 .BR strcmp ()
  46 function compares the two strings
  47 .I s1
  48 and
  49 .IR s2 .
  50 The locale is not taken into account (for a locale-aware comparison, see
  51 .BR strcoll (3)).
  52 It returns an integer less than, equal to, or greater
  53 than zero if
  54 .I s1
  55 is found, respectively, to be less than,
  56 to match, or be greater than
  57 .IR s2 .
  58 .PP
  59 The
  60 .BR strncmp ()
  61 function is similar, except it compares
  62 only the first (at most)
  63 .IR n
  64 bytes of
  65 .I s1
  66 and
  67 .IR s2 .
  68 .SH RETURN VALUE
  69 The
  70 .BR strcmp ()
  71 and
  72 .BR strncmp ()
  73 functions return an integer
  74 less than, equal to, or greater than zero if
  75 .I s1
  76 (or the first
  77 .I n
  78 bytes thereof) is found, respectively, to be less than, to
  79 match, or be greater than
  80 .IR s2 .
  81 .SH ATTRIBUTES
  82 For an explanation of the terms used in this section, see
  83 .BR attributes (7).
  84 .TS
  85 allbox;
  86 lbw19 lb lb
  87 l l l.
  88 Interface       Attribute       Value
  89 T{
  90 .BR strcmp (),
  91 .BR strncmp ()
  92 T}      Thread safety   MT-Safe
  93 .TE
  94 .SH CONFORMING TO
  95 POSIX.1-2001, POSIX.1-2008, C89, C99, SVr4, 4.3BSD.
  96 .SH SEE ALSO
  97 .BR bcmp (3),
  98 .BR memcmp (3),
  99 .BR strcasecmp (3),
 100 .BR strcoll (3),
 101 .BR string (3),
 102 .BR strncasecmp (3),
 103 .BR strverscmp (3),
 104 .BR wcscmp (3),
 105 .BR wcsncmp (3)