string/FreeBSD/strcmp.3

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  32 .\"     @(#)strcmp.3    8.1 (Berkeley) 6/4/93
  33 .\" $FreeBSD: src/lib/libc/string/strcmp.3,v 1.13 2009/12/04 09:20:20 trhodes Exp $
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  35 .Dd October 11, 2001
  36 .Dt STRCMP 3
  37 .Os
  38 .Sh NAME
  39 .Nm strcmp ,
  40 .Nm strncmp
  41 .Nd compare strings
  42 .Sh LIBRARY
  43 .Lb libc
  44 .Sh SYNOPSIS
  45 .In string.h
  46 .Ft int
  47 .Fo strcmp
  48 .Fa "const char *s1"
  49 .Fa "const char *s2"
  50 .Fc
  51 .Ft int
  52 .Fo strncmp
  53 .Fa "const char *s1"
  54 .Fa "const char *s2"
  55 .Fa "size_t n"
  56 .Fc
  57 .Sh DESCRIPTION
  58 The
  59 .Fn strcmp
  60 and
  61 .Fn strncmp
  62 functions
  63 lexicographically compare the null-terminated strings
  64 .Fa s1
  65 and
  66 .Fa s2 .
  67 .Pp
  68 The
  69 .Fn strncmp
  70 function
  71 compares not more than
  72 .Fa n
  73 characters.
  74 Because
  75 .Fn strncmp
  76 is designed for comparing strings rather than binary data,
  77 characters that appear after a
  78 .Ql \e0
  79 character are not compared.
  80 .Sh RETURN VALUES
  81 The
  82 .Fn strcmp
  83 and
  84 .Fn strncmp
  85 functions return an integer greater than, equal to, or less than 0, according
  86 as the string
  87 .Fa s1
  88 is greater than, equal to, or less than the string
  89 .Fa s2 .
  90 The comparison is done using unsigned characters, so that
  91 .Ql \e200
  92 is greater than
  93 .Ql \e0 .
  94 .Sh SEE ALSO
  95 .Xr bcmp 3 ,
  96 .Xr memcmp 3 ,
  97 .Xr strcasecmp 3 ,
  98 .Xr strcoll 3 ,
  99 .Xr strxfrm 3 ,
 100 .Xr wcscmp 3
 101 .Sh STANDARDS
 102 The
 103 .Fn strcmp
 104 and
 105 .Fn strncmp
 106 functions
 107 conform to
 108 .St -isoC .