Libc-583.tar.gz

[apple/libc.git] / string / wcscoll.3

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.\"     @(#)strcoll.3	8.1 (Berkeley) 6/4/93
.\" FreeBSD: src/lib/libc/string/strcoll.3,v 1.11 2001/10/01 16:09:00 ru Exp
.\" $FreeBSD: src/lib/libc/string/wcscoll.3,v 1.2 2002/12/09 14:04:05 ru Exp $
.\"
.Dd October 4, 2002
.Dt WCSCOLL 3
.Os
.Sh NAME
.Nm wcscoll ,
.Nm wcscoll_l
.Nd compare wide strings according to current collation
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In wchar.h
.Ft int
.Fo wcscoll
.Fa "const wchar_t *ws1"
.Fa "const wchar_t *ws2"
.Fc
.In wchar.h
.In xlocale.h
.Ft int
.Fo wcscoll_l
.Fa "const wchar_t *ws1"
.Fa "const wchar_t *ws2"
.Fa "locale_t loc"
.Fc
.Sh DESCRIPTION
The
.Fn wcscoll
function compares the null-terminated strings
.Fa ws1
and
.Fa ws2 ,
according to the current locale's collation order.
In the
.Dq Li C
locale,
.Fn wcscoll
is equivalent to
.Fn wcscmp .
.Pp
Although the
.Fn wcscoll
function uses the current locale, the
.Fn wcscoll_l
function may be passed a locale directly. See
.Xr xlocale 3
for more information.
.Sh RETURN VALUES
The
.Fn wcscoll
function
returns an integer greater than, equal to, or less than 0,
if
.Fa ws1
is greater than, equal to, or less than
.Fa ws2 .
.Pp
No return value is reserved to indicate errors;
callers should set
.Va errno
to 0 before calling
.Fn wcscoll .
If it is non-zero upon return from
.Fn wcscoll ,
an error has occurred.
.Sh ERRORS
The
.Fn wcscoll
function will fail if:
.Bl -tag -width Er
.It Bq Er EILSEQ
An invalid wide character code was specified.
.It Bq Er ENOMEM
Cannot allocate enough memory for temporary buffers.
.El
.Sh SEE ALSO
.Xr setlocale 3 ,
.Xr strcoll 3 ,
.Xr wcscmp 3 ,
.Xr wcsxfrm 3 ,
.Xr xlocale 3
.Sh STANDARDS
The
.Fn wcscoll
function
conforms to
.St -isoC-99 .
.Sh BUGS
The current implementation of
.Fn wcscoll
only works in single-byte
.Dv LC_CTYPE
locales, and falls back to using
.Fn wcscmp
in locales with extended character sets.