string/FreeBSD/strcasecmp.3

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  30 .\"     @(#)strcasecmp.3        8.1 (Berkeley) 6/9/93
  31 .\" $FreeBSD: src/lib/libc/string/strcasecmp.3,v 1.13 2009/04/07 13:42:53 trasz Exp $
  32 .\"
  33 .Dd June 9, 1993
  34 .Dt STRCASECMP 3
  35 .Os
  36 .Sh NAME
  37 .Nm strcasecmp ,
  38 .Nm strcasecmp_l ,
  39 .Nm strncasecmp ,
  40 .Nm strncasecmp_l
  41 .Nd compare strings, ignoring case
  42 .Sh LIBRARY
  43 .Lb libc
  44 .Sh SYNOPSIS
  45 .In strings.h
  46 .Ft int
  47 .Fo strcasecmp
  48 .Fa "const char *s1"
  49 .Fa "const char *s2"
  50 .Fc
  51 .Ft int
  52 .Fo strncasecmp
  53 .Fa "const char *s1"
  54 .Fa "const char *s2"
  55 .Fa "size_t n"
  56 .Fc
  57 .In strings.h
  58 .In xlocale.h
  59 .Ft int
  60 .Fo strcasecmp_l
  61 .Fa "const char *s1"
  62 .Fa "const char *s2"
  63 .Fa "locale_t loc"
  64 .Fc
  65 .Ft int
  66 .Fo strncasecmp_l
  67 .Fa "const char *s1"
  68 .Fa "const char *s2"
  69 .Fa "size_t n"
  70 .Fa "locale_t loc"
  71 .Fc
  72 .Sh DESCRIPTION
  73 The
  74 .Fn strcasecmp
  75 and
  76 .Fn strncasecmp
  77 functions
  78 compare the null-terminated strings
  79 .Fa s1
  80 and
  81 .Fa s2 .
  82 .Pp
  83 The
  84 .Fn strncasecmp
  85 compares at most
  86 .Fa n
  87 characters.
  88 .Pp
  89 Although the
  90 .Fn strcasecmp
  91 and
  92 .Fn strncasecmp
  93 functions use the current locale, the
  94 .Fn strcasecmp_l
  95 and
  96 .Fn strncasecmp_l
  97 functions may be passed locales directly. See
  98 .Xr xlocale 3
  99 for more information.
 100 .Sh RETURN VALUES
 101 The
 102 .Fn strcasecmp
 103 and
 104 .Fn strncasecmp
 105 return an integer greater than, equal to, or less than 0,
 106 according as
 107 .Fa s1
 108 is lexicographically greater than, equal to, or less than
 109 .Fa s2
 110 after translation of each corresponding character to lower-case.
 111 The strings themselves are not modified.
 112 The comparison is done using unsigned characters, so that
 113 .Sq Li \e200
 114 is greater than
 115 .Ql \e0 .
 116 .Sh SEE ALSO
 117 .Xr bcmp 3 ,
 118 .Xr memcmp 3 ,
 119 .Xr strcmp 3 ,
 120 .Xr strcoll 3 ,
 121 .Xr strxfrm 3 ,
 122 .Xr tolower 3 ,
 123 .Xr xlocale 3
 124 .Sh HISTORY
 125 The
 126 .Fn strcasecmp
 127 and
 128 .Fn strncasecmp
 129 functions first appeared in
 130 .Bx 4.4 .
 131 Their prototypes existed previously in
 132 .In string.h
 133 before they were moved to
 134 .In strings.h
 135 for
 136 .St -p1003.1-2001
 137 compliance.