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 .Fn strcmp "const char *s1" "const char *s2"
  52 .Ft int
  53 .Fn strncmp "const char *s1" "const char *s2" "size_t len"
  54 .Sh DESCRIPTION
  55 The
  56 .Fn strcmp
  57 and
  58 .Fn strncmp
  59 functions
  60 lexicographically compare the null-terminated strings
  61 .Fa s1
  62 and
  63 .Fa s2 .
  64 .Pp
  65 The
  66 .Fn strncmp
  67 function
  68 compares not more than
  69 .Fa len
  70 characters.
  71 Because
  72 .Fn strncmp
  73 is designed for comparing strings rather than binary data,
  74 characters that appear after a
  75 .Ql \e0
  76 character are not compared.
  77 .Sh RETURN VALUES
  78 The
  79 .Fn strcmp
  80 and
  81 .Fn strncmp
  82 return an integer greater than, equal to, or less than 0, according
  83 as the string
  84 .Fa s1
  85 is greater than, equal to, or less than the string
  86 .Fa s2 .
  87 The comparison is done using unsigned characters, so that
  88 .Ql \e200
  89 is greater than
  90 .Ql \e0 .
  91 .Sh SEE ALSO
  92 .Xr bcmp 3 ,
  93 .Xr memcmp 3 ,
  94 .Xr strcasecmp 3 ,
  95 .Xr strcoll 3 ,
  96 .Xr strxfrm 3
  97 .Sh STANDARDS
  98 The
  99 .Fn strcmp
 100 and
 101 .Fn strncmp
 102 functions
 103 conform to
 104 .St -isoC .