string/strcasecmp.3

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  34 .\"     @(#)strcasecmp.3        8.1 (Berkeley) 6/9/93
  35 .\" $FreeBSD: src/lib/libc/string/strcasecmp.3,v 1.11 2003/09/08 19:57:15 ru Exp $
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  37 .Dd June 9, 1993
  38 .Dt STRCASECMP 3
  39 .Os
  40 .Sh NAME
  41 .Nm strcasecmp ,
  42 .Nm strcasecmp_l ,
  43 .Nm strncasecmp ,
  44 .Nm strncasecmp_l
  45 .Nd compare strings, ignoring case
  46 .Sh LIBRARY
  47 .Lb libc
  48 .Sh SYNOPSIS
  49 .In strings.h
  50 .Ft int
  51 .Fo strcasecmp
  52 .Fa "const char *s1"
  53 .Fa "const char *s2"
  54 .Fc
  55 .Ft int
  56 .Fo strncasecmp
  57 .Fa "const char *s1"
  58 .Fa "const char *s2"
  59 .Fa "size_t n"
  60 .Fc
  61 .In strings.h
  62 .In xlocale.h
  63 .Ft int
  64 .Fo strcasecmp_l
  65 .Fa "const char *s1"
  66 .Fa "const char *s2"
  67 .Fa "locale_t loc"
  68 .Fc
  69 .Ft int
  70 .Fo strncasecmp_l
  71 .Fa "const char *s1"
  72 .Fa "const char *s2"
  73 .Fa "size_t n"
  74 .Fa "locale_t loc"
  75 .Fc
  76 .Sh DESCRIPTION
  77 The
  78 .Fn strcasecmp
  79 and
  80 .Fn strncasecmp
  81 functions
  82 compare the null-terminated strings
  83 .Fa s1
  84 and
  85 .Fa s2 .
  86 .Pp
  87 The
  88 .Fn strncasecmp
  89 compares at most
  90 .Fa n
  91 characters.
  92 .Pp
  93 Although the
  94 .Fn strcasecmp
  95 and
  96 .Fn strncasecmp
  97 functions use the current locale, the
  98 .Fn strcasecmp_l
  99 and
 100 .Fn strncasecmp_l
 101 functions may be passed locales directly. See
 102 .Xr xlocale 3
 103 for more information.
 104 .Sh RETURN VALUES
 105 The
 106 .Fn strcasecmp
 107 and
 108 .Fn strncasecmp
 109 return an integer greater than, equal to, or less than 0,
 110 according as
 111 .Fa s1
 112 is lexicographically greater than, equal to, or less than
 113 .Fa s2
 114 after translation of each corresponding character to lower-case.
 115 The strings themselves are not modified.
 116 The comparison is done using unsigned characters, so that
 117 .Sq Li \e200
 118 is greater than
 119 .Ql \e0 .
 120 .Sh SEE ALSO
 121 .Xr bcmp 3 ,
 122 .Xr memcmp 3 ,
 123 .Xr strcmp 3 ,
 124 .Xr strcoll 3 ,
 125 .Xr strxfrm 3 ,
 126 .Xr tolower 3 ,
 127 .Xr xlocale 3
 128 .Sh HISTORY
 129 The
 130 .Fn strcasecmp
 131 and
 132 .Fn strncasecmp
 133 functions first appeared in
 134 .Bx 4.4 .
 135 Their prototypes existed previously in
 136 .In string.h
 137 before they were moved to
 138 .In strings.h
 139 for
 140 .St -p1003.1-2001
 141 compliance.