string/strcmp.3

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  36 .\"     @(#)strcmp.3    8.1 (Berkeley) 6/4/93
  37 .\" $FreeBSD: src/lib/libc/string/strcmp.3,v 1.10 2001/10/11 17:02:44 mike Exp $
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  39 .Dd October 11, 2001
  40 .Dt STRCMP 3
  41 .Os
  42 .Sh NAME
  43 .Nm strcmp ,
  44 .Nm strncmp
  45 .Nd compare strings
  46 .Sh LIBRARY
  47 .Lb libc
  48 .Sh SYNOPSIS
  49 .In string.h
  50 .Ft int
  51 .Fo strcmp
  52 .Fa "const char *s1"
  53 .Fa "const char *s2"
  54 .Fc
  55 .Ft int
  56 .Fo strncmp
  57 .Fa "const char *s1"
  58 .Fa "const char *s2"
  59 .Fa "size_t n"
  60 .Fc
  61 .Sh DESCRIPTION
  62 The
  63 .Fn strcmp
  64 and
  65 .Fn strncmp
  66 functions
  67 lexicographically compare the null-terminated strings
  68 .Fa s1
  69 and
  70 .Fa s2 .
  71 .Pp
  72 The
  73 .Fn strncmp
  74 function
  75 compares not more than
  76 .Fa n
  77 characters.
  78 Because
  79 .Fn strncmp
  80 is designed for comparing strings rather than binary data,
  81 characters that appear after a
  82 .Ql \e0
  83 character are not compared.
  84 .Sh RETURN VALUES
  85 The
  86 .Fn strcmp
  87 and
  88 .Fn strncmp
  89 return an integer greater than, equal to, or less than 0, according
  90 as the string
  91 .Fa s1
  92 is greater than, equal to, or less than the string
  93 .Fa s2 .
  94 The comparison is done using unsigned characters, so that
  95 .Ql \e200
  96 is greater than
  97 .Ql \e0 .
  98 .Sh SEE ALSO
  99 .Xr bcmp 3 ,
 100 .Xr memcmp 3 ,
 101 .Xr strcasecmp 3 ,
 102 .Xr strcoll 3 ,
 103 .Xr strxfrm 3
 104 .Sh STANDARDS
 105 The
 106 .Fn strcmp
 107 and
 108 .Fn strncmp
 109 functions
 110 conform to
 111 .St -isoC .