.\" Copyright (c) 1993 .\" The Regents of the University of California. All rights reserved. .\" .\" This code is derived from software contributed to Berkeley by .\" Paul Borman at Krystal Technologies. .\" .\" 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. .\" 3. All advertising materials mentioning features or use of this software .\" must display the following acknowledgement: .\" This product includes software developed by the University of .\" California, Berkeley and its contributors. .\" 4. Neither the name of the University nor the names of its contributors .\" may be used to endorse or promote products derived from this software .\" without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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. .\" .\" @(#)rune.3 8.2 (Berkeley) 12/11/93 .\" $FreeBSD: src/lib/libc/locale/rune.3,v 220.127.116.11 2001/12/14 18:33:54 ru Exp $ .\" .Dd December 11, 1993 .Dt RUNE 3 .Os .Sh NAME .Nm setrunelocale , .Nm setinvalidrune , .Nm sgetrune , .Nm sputrune , .Nm fgetrune , .Nm fungetrune , .Nm fputrune .Nd rune support for C .Sh LIBRARY .Lb libc .Sh SYNOPSIS .In rune.h .In errno.h .Ft int .Fn setrunelocale "char *locale" .Ft void .Fn setinvalidrune "rune_t rune" .Ft rune_t .Fn sgetrune "const char *string" "size_t n" "char const **result" .Ft int .Fn sputrune "rune_t rune" "char *string" "size_t n" "char **result" .Pp .In stdio.h .Ft long .Fn fgetrune "FILE *stream" .Ft int .Fn fungetrune "rune_t rune" "FILE *stream" .Ft int .Fn fputrune "rune_t rune" "FILE *stream" .Sh DESCRIPTION The .Fn setrunelocale controls the type of encoding used to represent runes as multibyte strings as well as the properties of the runes as defined in .Aq Pa ctype.h . The .Fa locale argument indicates which locale to load. If the locale is successfully loaded, .Dv 0 is returned, otherwise an errno value is returned to indicate the type of error. .Pp The .Fn setinvalidrune function sets the value of the global value .Dv _INVALID_RUNE to be .Fa rune . .Pp The .Fn sgetrune function tries to read a single multibyte character from .Fa string , which is at most .Fa n bytes long. If .Fn sgetrune is successful, the rune is returned. If .Fa result is not .Dv NULL , .Fa *result will point to the first byte which was not converted in .Fa string . If the first .Fa n bytes of .Fa string do not describe a full multibyte character, .Dv _INVALID_RUNE is returned and .Fa *result will point to .Fa string . If there is an encoding error at the start of .Fa string , .Dv _INVALID_RUNE is returned and .Fa *result will point to the second character of .Fa string . .Pp the .Fn sputrune function tries to encode .Fa rune as a multibyte string and store it at .Fa string , but no more than .Fa n bytes will be stored. If .Fa result is not .Dv NULL , .Fa *result will be set to point to the first byte in string following the new multibyte character. If .Fa string is .Dv NULL , .Fa *result will point to .Dv "(char *)0 +" .Fa x , where .Fa x is the number of bytes that would be needed to store the multibyte value. If the multibyte character would consist of more than .Fa n bytes and .Fa result is not .Dv NULL , .Fa *result will be set to .Dv NULL . In all cases, .Fn sputrune will return the number of bytes which would be needed to store .Fa rune as a multibyte character. .Pp The .Fn fgetrune function operates the same as .Fn sgetrune with the exception that it attempts to read enough bytes from .Fa stream to decode a single rune. It returns either .Dv EOF on end of file, .Dv _INVALID_RUNE on an encoding error, or the rune decoded if all went well. .Pp The .Fn fungetrune function pushes the multibyte encoding, as provided by .Fn sputrune , of .Fa rune onto .Fa stream such that the next .Fn fgetrune call will return .Fa rune . It returns .Dv EOF if it fails and .Dv 0 on success. .Pp The .Fn fputrune function writes the multibyte encoding of .Fa rune , as provided by .Fn sputrune , onto .Fa stream . It returns .Dv EOF on failure and .Dv 0 on success. .Sh RETURN VALUES The .Fn setrunelocale function returns one of the following values: .Bl -tag -width Er .It Er 0 .Fn setrunelocale was successful. .It Bq Er EFAULT .Fa locale was .Dv NULL . .It Bq Er ENOENT The locale could not be found. .It Bq Er EFTYPE The file found was not a valid file. .It Bq Er EINVAL The encoding indicated by the locale was unknown. .El .Pp The .Fn sgetrune function either returns the rune read or .Dv _INVALID_RUNE . The .Fn sputrune function returns the number of bytes needed to store .Fa rune as a multibyte string. .Sh FILES .Bl -tag -width /usr/share/locale/locale/LC_CTYPE -compact .It Pa $PATH_LOCALE/ Ns Em locale Ns /LC_CTYPE .It Pa /usr/share/locale/ Ns Em locale Ns /LC_CTYPE binary LC_CTYPE file for the locale .Em locale . .El .Sh SEE ALSO .Xr mbrune 3 , .Xr setlocale 3 , .Xr euc 4 , .Xr utf2 4 .Sh NOTES The ANSI C type .Em wchar_t is the same as .Em rune_t . .Em Rune_t was chosen to accent the purposeful choice of not basing the system with the ANSI C primitives, which were, shall we say, less aesthetic. .Sh HISTORY These functions first appeared in .Bx 4.4 . .Pp The .Fn setrunelocale function and the other non-ANSI rune functions were inspired by .Sy "Plan 9 from Bell Labs" as a much more sane alternative to the ANSI multibyte and wide character support. .\"They were conceived at the San Diego 1993 Summer USENIX conference by .\"Paul Borman of Krystal Technologies, Keith Bostic of CSRG and Andrew Hume .\"of Bell Labs. .Pp All of the ANSI multibyte and wide character support functions are built using the rune functions.