freebsd-dev/lib/libc/locale/utf2.4
Steve Price 0ce1971c2a Correct description of which runes are encoded as two bytes.
PR:		4555
Submitted by:	Dmitrij Tejblum <tejblum@arc.hq.cti.ru>

[0x0400 - 0xffff] [bbbbbbbb.bbbbbbbb] -> 1110bbbb, 10bbbbbb, 10bbbbbb
.Ed
.Pp
If more than a single representation of a value exists (for example,
0x00; 0xC0 0x80; 0xE0 0x80 0x80) the shortest representation is always
used (but the longer ones will be correctly decoded).
.Pp
The final three encodings provided by X-Open:
.Bd -literal
[00000000.000bbbbb.bbbbbbbb.bbbbbbbb] ->
	11110bbb, 10bbbbbb, 10bbbbbb, 10bbbbbb

[000000bb.bbbbbbbb.bbbbbbbb.bbbbbbbb] ->
	111110bb, 10bbbbbb, 10bbbbbb, 10bbbbbb, 10bbbbbb

[0bbbbbbb.bbbbbbbb.bbbbbbbb.bbbbbbbb] ->
	1111110b, 10bbbbbb, 10bbbbbb, 10bbbbbb, 10bbbbbb, 10bbbbbb
.Ed
.Pp
which provides for the entire proposed ISO-10646 31 bit standard are currently
not implemented.
.Sh "SEE ALSO"
.Xr mklocale 1 ,
.Xr setlocale 3
@


1.4
log
@Don't use hardcoded *roff font change requests.  Do it
via mdoc macros instead.
@
text
@d37 1
a37 1
.Dd "June 4, 1993"
@


1.3
log
@Very minor mdoc cleanup.
@
text
@d44 2
a45 1
\fBENCODING "UTF2"\fP
@


1.2
log
@Another round of various man page cleanups.
@
text
@d65 1
a65 1
.sp
d81 1
a81 1
.sp
@


1.2.2.1
log
@YAMFC:

Commit all of the -current changes that apply to 2.2.  These fall into
several categories:

- Cosmetic/mdoc changes.  They don't really afect the output
  at all, but having them in 2.2 will make it easier to diff the man
  pages later when looking for real changes.
- Update some man pages to reflect the current 2.2 header files.
- Sort xrefs.
- A few typo fixes.
- And a few changes that actualy added text to the man page that should
  be reflected in 2.2.
- Add some missing MLINKS.

Requested by: bde
@
text
@d44 1
a44 2
.Nm ENCODING
.Qq UTF2
d65 1
a65 1
.Pp
d81 1
a81 1
.Pp
@


1.2.2.2
log
@MFC:  Just the locale fixes (small doc tweaks for the most part)
and the new strptime(3) call.  Having added something, does this
require a version bump?  Haven't we bumped once already?

There are a *LOT* of additional 3.0 changes to be merged but I'm not
entirely comfortable with some of them so I'll take the conservative
(read: cowardly :) way out and just merge this much.
@
text
@d37 1
a37 1
.Dd June 4, 1993
@


1.1
log
@Initial revision
@
text
@d41 1
a41 1
.Nm UTF2
@


1.1.1.1
log
@BSD 4.4 Lite Lib Sources
@
text
@@


1.1.1.1.6.1
log
@Phase 2 of merge - also fix things broken in phase 1.
Watch out for falling rock until phase 3 is over!

libc completely merged except for phkmalloc & rfork (don't know if David
wants that).

Some include files in sys/ had to be updated in order to bring in libc.
@
text
@d41 1
a41 1
.Nm utf2
@


1.1.1.1.6.2
log
@This 3rd mega-commit should hopefully bring us back to where we were.
I can get it to `make world' succesfully, anyway!
@
text
@d41 1
a41 1
.Nm UTF2
@
1997-11-05 04:18:42 +00:00

88 lines
3.6 KiB
Groff

.\" 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.
.\"
.\" @(#)utf2.4 8.1 (Berkeley) 6/4/93
.\"
.Dd June 4, 1993
.Dt UTF2 4
.Os
.Sh NAME
.Nm utf2
.Nd "Universal character set Transformation Format encoding of runes
.Sh SYNOPSIS
.Nm ENCODING
.Qq UTF2
.Sh DESCRIPTION
The
.Nm UTF2
encoding is based on a proposed X-Open multibyte
\s-1FSS-UCS-TF\s+1 (File System Safe Universal Character Set Transformation Format) encoding as used in
.Nm Plan 9 from Bell Labs.
Although it is capable of representing more than 16 bits,
the current implementation is limited to 16 bits as defined by the
Unicode Standard.
.Pp
.Nm UTF2
representation is backwards compatible with ASCII, so 0x00-0x7f refer to the
ASCII character set. The multibyte encoding of runes between 0x0080 and 0xffff
consist entirely of bytes whose high order bit is set. The actual
encoding is represented by the following table:
.Bd -literal
[0x0000 - 0x007f] [00000000.0bbbbbbb] -> 0bbbbbbb
[0x0080 - 0x07ff] [00000bbb.bbbbbbbb] -> 110bbbbb, 10bbbbbb
[0x0800 - 0xffff] [bbbbbbbb.bbbbbbbb] -> 1110bbbb, 10bbbbbb, 10bbbbbb
.Ed
.Pp
If more than a single representation of a value exists (for example,
0x00; 0xC0 0x80; 0xE0 0x80 0x80) the shortest representation is always
used (but the longer ones will be correctly decoded).
.Pp
The final three encodings provided by X-Open:
.Bd -literal
[00000000.000bbbbb.bbbbbbbb.bbbbbbbb] ->
11110bbb, 10bbbbbb, 10bbbbbb, 10bbbbbb
[000000bb.bbbbbbbb.bbbbbbbb.bbbbbbbb] ->
111110bb, 10bbbbbb, 10bbbbbb, 10bbbbbb, 10bbbbbb
[0bbbbbbb.bbbbbbbb.bbbbbbbb.bbbbbbbb] ->
1111110b, 10bbbbbb, 10bbbbbb, 10bbbbbb, 10bbbbbb, 10bbbbbb
.Ed
.Pp
which provides for the entire proposed ISO-10646 31 bit standard are currently
not implemented.
.Sh "SEE ALSO"
.Xr mklocale 1 ,
.Xr setlocale 3