version

这是一个同样来自贝尔实验室的和UNIX有着渊源的操作系统, 其简洁的设计和实现易于我们学习和理解

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Version 3.3.2   7/7/92
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 1: Added UTF support for Plan 9. Only signigficant source code changes were
    in dpost.utf (font.h, font.c, dpost.c). Added common/rune.[hc] so code
    can be compiled elsewere. Remove RUNELIB in commmon/rune.h if fullrune(),
    chartorune(), and runetochar() are available on your system. Original
    DWB 3.3 dpost source is in directory dpost. You should select dpost or
    dpost.utf in postscript.mk. Both compile and install a program called
    dpost so don't pick both!

 2: dpost can read old or UTF troff output. Default is whatever is assigned
    to READING (file common/gen.h). You get one or the other, unless troff
    tells dpost what encoding to use (currently x E UTF).

 3: Most other translators passed bytes through and so only needed slightly
    modified proglogues and a new encoding scheme (psencoding/UTF.enc). It
    works for Latin1, but still needs a bit more attention. Prologue changes
    were easy and only involved adding lines like,

	/show {show} bind def
	/stringwidth {stringwidth} bind def

    Guarantees text procedures used in prologues aren't operators and can be
    successfully redefined in UTF.enc. Unbinding means a small but probably
    not noticeable speed penalty. You may not want to include those changes
    on other system.

 4: Operator redefinitions means dpost should work in it's own dictionary
    (rather than userdict). Not implemented yet, but should be easy. Only
    potential problem is with picture inclusion when dpost reads UTF.enc.

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Version 3.3.2   5/15/92
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 1: postio now outputs all unrecognized status reports - primarly for spooler
    accounting purposes.

 2: The makefiles also enable the selection of alternate stream module names
    for streams based DKHOST support in postio.

 3: dpost now assumes the optional fifth token in a font mounting command
    (e.g. x font 2 R /usr/me/font/R) is the full pathname of the font. troff
    outputs the pathname when a .fp request contains a third argument that
    begins with a / as in .fp 1 R /usr/me/font/R.

 4: By request Latin1's - character has been changed from minus to the smaller
    hyphen character. Added \(dq and \(bs (for " and \ characters) to devpost
    and devLatin1 tables. Also added \(!! and \(?? to devpost tables.

 5: Helvetica-Light and Helvetica-LightOblique tables are included as HL and
    HK in devpost and devLatin1, even though fonts aren't generally available.
    Also copy H to HM during an install of devpost and devLatin1 tables.

 6: LH is a horizontally arranged color Lucent logo with text which replaces the AT&T logo.
    LV is a vertically arranged monochrome AT&T logo with text.
    FA is a horizontally arranged monochrome Lucent logo with text (low res.).
	L1 is a monochrome AT&T logo, no text.
	LA is a monochrome AT&T text.

 7: Included L1 and LA outlines in devpost and devLatin1. Adjusted LA scaling
    so size of "AT&T" matches what's in LV. Original PostScript came
    from Matthijs Melchior.

 8: Included the "symmetric clippath" version of roundpage.ps as Nroundpage.ps
    in directory postscript/psfiles. Move it to roundpage.ps if you want it to
    be the default.

 9: Added a few lines of code to dpost for handling current implementation of
    the portrait/landscape mode macros.

10: The man page for download now documents the -r option and notes that -p
    is for Unix 4.0 lp.

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Version 3.3.1   4/30/91
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 1: buildtables stuff has been cleaned up and is now a user level command.
    Uses shell.lib files that are installed with font tables. The devpost
    tables were built on a version 47.0 PS-810. The devLatin1 tables were
    built on a version 51.7 PS-820.

 2: The devLatin1 tables provide support for the ISO Latin1 alphabet on
    PostScript printers.

 3: All translators support different text font encoding schemes using the
    -E option and *.enc files installed in POSTLIB. The ISO Latin 1 alphabet
    is supported with file /usr/lib/postscript/Latin1.enc.

 4: printfont prints a table of the available (encoded) characters in one
    or more PostScript fonts. It also understands the -E option.

 5: grabit and hardcopy are two new programs that may be of interest to the
    more serious PostScript programmer. grabit resembles ==, but produces
    output that's usally easier to read. hardcopy redirects output from
    PostScript file output operators (or procedures) to paper. It's useful
    if you don't have direct access to a printer.

 6: Prologues and programs are stored together. Other common PostScript files
    are now in the psfiles directory.

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Verions 3.3	4/16/90
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 1: The package is now included in DWB. Version numbers are a bit misleading.
    The one in postscript.mk refers to the DWB package.

 2: dpost (and troff) now read ASCII font tables. makedev and the old binary
    format are gone.

 3: The devpost directory came directly from the DWB package. The font tables
    originally distributed with this package are in directory devopost. They
    are not installed. If possible we recommend you use the devpost tables.
    The old tables can be installed by adding devopost to the TARGETS list in
    file postscript.mk.

 4: dpost recognizes two new fields in font tables. Entries for the full
    PostScript font look like,

		fontname Times-Roman

    The fontname field is helps manage host resident fonts, the DocumentFonts
    comment, and is used to define font name abbreviations like the ones in
    dpost.ps. A font table entry that looks like,

		named in prologue

    disables the runtime abbreviation for the font - dpost assumes it's already
    in the prologue.

 5: Extra font tables included in DWB 3.0's devpost font collection are in
    directory devpost.add. They included here, but should probably not be
    used.

 6: Bracket building has been fixed and tested on a wide range of PostScript
    printers. It will likely still not work on many clones. Real problem
    appears to be with Adobe's braceleftbt character.

 7: Most of the special tuning code for device emulation has been removed.
    Emulation still works, but there may be cases where it's not as good as
    earlier versions.

 8: Several problems with color and reverse video printing have been fixed.

 9: buildtables directory has been cleanup up. The template files in directory
    buildtables/devpost.data were used to build the devpost tables.

10: postplot and download are two new programs. postplot is for the System V
    plot package only. Both were written for the Unix 4.0 lp package.

11: postgif is also relatively new - it came from Chi Choy.

12: The translators now rotate clockwise when printing in landscape mode. If
    you want the old behavior set ROTATION to -1 in postscript.mk.

13: forms.ps has been cleaned up some. Better behavior when you print 2
    landscape pages on one sheet.

14: Handling of Datakit code for System V has been changed some. Makefiles
    now expect to find libdk.a and dk.h in standard places (e.g /usr/lib and
    /usr/include). Set DKHOST to TRUE in postscript.mk to get Datakit support
    on System V.

    If you're stuck and need to have things behave as they did in the past
    take a look at file postio/postio.mk. Define DKHOSTDIR and uncomment
    three lines and the behavior should be close to what it was.

15: Picture inclusion and color macros are gone. They're included in the DWB
    package, and not here.

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Version 3.2	11/27/89
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 1: Implemented height and slant requests in dpost.

 2: Modified the behavior of all translators so save objects are no longer left
    on the stack. The original implementation was a mistake and occasionally
    (e.g. picture inclusion with forms.ps) resulted in invalid restores.

 3: Fixed the mistake in the external declaration of mesg in postio/slowsend.c.

 4: The malloc() call in postdmd (routine dimensions()) is only made if patterns