Add a function to iterate over all characters in a particular character

class. This is necessary in order to implement tr(1) efficiently in
multibyte locales, since the brute force method of finding all characters
in a class is infeasible with a 32-bit (or wider) wchar_t.

1 files changed, 58 insertions, 0 deletions

diff --git a/lib/libc/locale/nextwctype.3 b/lib/libc/locale/nextwctype.3
new file mode 100644
index 0000000..2d9acd1
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+++ b/lib/libc/locale/nextwctype.3
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+.\"
+.\" Copyright (c) 2004 Tim J. Robbins
+.\" All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\" $FreeBSD$
+.\"
+.Dd July 8, 2004
+.Dt NEXTWCTYPE 3
+.Os
+.Sh NAME
+.Nm nextwctype
+.Nd "iterate through character classes"
+.Sh LIBRARY
+.Lb libc
+.Sh SYNOPSIS
+.In wctype.h
+.Ft wint_t
+.Fo nextwctype
+.Fa "wint_t ch" "wctype_t wct"
+.Fc
+.Sh DESCRIPTION
+The
+.Fn nextwctype
+function determines the next character after
+.Fa ch
+that is a member of character class
+.Fa wct .
+If
+.Fa ch
+is \-1, the search begins at the first member of
+.Fa wct .
+.Sh RETURN VALUES
+The
+.Fn nextwctype
+functions returns the next character, or \-1 if there are no more.
+.Sh SEE ALSO
+.Xr wctype 3