cawf.1

Unix操作系统minix 2.0源码

.LP
There are appropriate
.B .^b
requests in the distribution
.BR man ,
.B me
and
.B ms
macro files.
(The
.B me
and
.B ms
macro files use another
.B .^b
request, \fB.^b NH\fP, to enable numbered header processing.)
.SH OUTPUT
The default output format supported by
.IR cawf ,
in its distributed form,
is that appropriate to a dumb terminal,
using overprinting for italics (via underlining) and bold.
The \*(Nr special characters are printed as some vague approximation
(it's sometimes extremely vague) to their correct appearance.
.PP
One part of
.IR cawf 's
knowledge of the output device, related to the formation of characters,
is established by a device file, which is read before the user's input.
The search for it begins in
.IR cawf 's
library directory, under the name \fIterm\fP.\fBdev\fP
(where \fIterm\fR is the value of the TERM environment variable).
Failing to find that,
.I cawf
searches for
.BR dumb.dev .
(See the
.B FILES
section for a description of the path to
.IR cawf 's
library directory.)
The device file
uses special internal requests
to set up resolution, special characters 
and more normal \*(Nr functions to set up page length, etc.
.PP
.I Cawf
has limited support for fonts special forms of bold and italic characters.
It is provided through the
.B \-c
.IR config ,
.BI \-d device
and
.BI \-f font
options.
See the
.B DEVICES
section for more information.
.PP
Note the distinction between the device and the output device configuration
files.
The device file typically defines characters and constant output parameters.
The output device configuration file defines font and type face codes.
It is usually not necessary to define a separate device file for each
device represented in the output device configuration file \- the
.I dumb.dev
device file will suffice for almost all representations.
.SH DEVICES
.I Cawf
supports primitive output device configuration for font and type face
control.
One font may be selected for the entire document by directing
.I cawf
to issue a font selection control character string at the beginning
of the document, and control character strings may be selected for
switching between the bold, italic and Roman type faces.
.PP
The
.B \-c
.IR config,
.BI \-d device
and
.BI \-f font
options direct the font and type face selections.
.PP
The
.BI \-d device
option specifies the name of the device.
.I Cawf
has three built\-in devices \- ANSI, NONE and NORMAL.
When the ANSI device is selected,
.I cawf
issues the ANSI shadow mode control codes, ``ESC [ 7 m'', to represent
the bold face;
the ANSI underscore control codes, ``ESC [ 4 m'', to represent the italic
face;
and the ANSI control codes, ``ESC [ 0 m'', to represent the ROMAN face.
No
.BI \-f font
specification is permitted with the ANSI device.
.PP
When the NONE device is selected,
.I cawf
uses no special output codes to represent the type faces.
No
.BI \-f font
specification is permitted with the ANSI device.
.PP
The NORMAL output device is the default.
When it's selected,
.I cawf
overprints each bold character two times, using three issuances of each
bold character, separated by backspace characters;
it issues an underscore and backspace before each italic character.
No
.BI \-f font
specification is permitted with the ANSI device.
The
.IR bsfilt (1)
filter may be used to further process the backspace codes output for
a NORMAL device.
.PP
All other devices named in the
.BI \-d device
option must be represented by a stanza in the device configuration file.
The device configuration file is usually contained in
.I device.cf
in
.IR cawf's
library directory (see the
.B FILES
section for more information).
An alternate device configuration file path may be specified with the
.BI \-c config
option.
.PP
The
.B DEVICE CONFIGURATION FILE
section describes the organization of the device configuration file.
It is easy to add devices to the
.I device.cf
supplied in the
.I cawf
distribution.
.PP
The
.BI \-f font
option may be used with the
.BI \-d device
option, when the appropriate stanza in the device configuration file
contains an entry for the named
.IR font .
The
.B DEVICE CONFIGURATION FILE
section describes how fonts are defined in device configuration file
stanzas.
.SH DEVICE CONFIGURATION FILE
The device configuration file defines the special character codes
necessary to direct output devices to select fonts and to produce
bold, italic and Roman type faces.
.PP
The configuration file is usually found in
.I device.cf
in
.IR cawf 's
library directory (see the
.B FILES
section for more information).
It is organized into two main parts \- comments and device stanzas.
Comments are any lines that begin with the pound sign (`#') character.
They are informational only and
.I cawf
ignores them.
.I Cawf
also ignores empty lines, so they may be used as vertical white space.
.PP
Stanzas name devices and define their font and type face control strings.
A stanza begins with the name of the device, starting at the beginning
of a line and occupying the entire line.
The body of the stanza, defining fonts and type faces, is formed of
lines beginning with white space (a TAB or space characters) that
directly follow the device name.
.PP
Individual lines of the stanza body contain a key character, followed
by a equal sign, followed by the font name (if a font key) and the
output device control codes.
.I Cawf
issues the font control codes once, at the beginning of output, so
only one font may be selected.
The type face control codes are issued at each change of type face.
.PP
The key characters are:
.ne 4
.DS
b	for bold
f	for font definition
i	for italic
r	for Roman
.DE
The `b', `i' and `r' key codes are followed by an equal sign (`=') and
their control code definition.
The `f' key code is followed by an equal sign (`='), the font name,
another equal sign and the font control code definition.
.PP
Control code definitions may contain any printable ASCII characters.
Non\-printable characters may be encoded in octal notation with the `\\nnn'
form or in hexadecimal with the `\\xnn' form.
The special code, `\\E' (or `\\e') represents the ESC control
character (\\033 or \\x1b).
.PP
Here's a sample showing the definition for the HP LaserJet III.
The stanza name is ``lj3''.
All its non\-printable characters are ESCs; the first is coded in
octal form; the second with '\\E'; the rest, in hexadecimal form.
TAB is used as the leading white space character for the stanza
body lines.
.DS
# HP LaserJet III

lj3
        b=\\033(s7B
        i=\\E(s1S
        r=\\x1b(s0B\\x1b(s0S
        f=c10=\x1b&l0O\x1b(8U\x1b(s0p12h10v0s0b3T
        f=c12ibm=\x1b&l0O\x1b(10U\x1b(s0p10.00h12.0v0s0b3T
        f=lg12=\x1b&l0O\x1b(8U\x1b(s12h12v0s0b6T
.DE
.PP
The distribution
.I device.cf
file defines the following devices and fonts.
.LP
.ta \w'kxp1180'u+3n +\w'Italic:'u+3n +\w'bps10'u+6n
.nf
.ne 3
epson	dot matrix printer in Epson FX-86e/FX-800 mode
	Bold:	Double-strike
	Fonts:	none

.ne 4
ibmppds	IBM Personal Printer Data Stream (PPDS) protocol
	Bold:	Double-strike
	Italic:	Underline
	Fonts:	none

.ne 12
kxp1124	Panasonic KX\-P1124 dot matrix printer in PGM mode
	Bold:	Emphasized
	Fonts:	c10	10 Characters Per Inch (CPI) Courier
		c12	12 CPI Courier
		bps10	10 CPI Bold PS
		bps12	12 CPI Bold PS
		p10	10 CPI Prestige
		p12	12 CPI Prestige
		s10	10 CPI Script
		s12	12 CPI Script
		ss10	10 CPI Sans Serif
		ss12	12 CPI Sans Serif

.ne 10
kxp1180	Panasonic KX\-P1180 dot matrix printer in PGM mode
	Bold:	Emphasized
	Fonts:	c10	10 Characters Per Inch (CPI) Courier
		c12	12 CPI Courier
		bps10	10 CPI Bold PS
		bps12	12 CPI Bold PS
		p10	10 CPI Prestige
		p12	12 CPI Prestige
		ss10	10 CPI Sans Serif
		ss12	12 CPI Sans Serif

.ne 6
lj3	HP LaserJet III
	Fonts:	c10	10 point, 12 Characters Per Inch (CPI)
			Courier
		c12ibm	12 point, 10 CPI Courier, IBM\-PC
			Symbol Set
		lg12	12 point, 12 CPI Letter Gothic

.ne 4
vgamono	VGA monochrome monitor for MS\-DOS
	(ANSI.SYS driver required for MS\-DOS)
	Italic:	Reverse-video
	Fonts:	none
.SH FILES
.I Cawf
resource files are located in the
.I cawf
library directory \- \fI C:\\SYS\\LIB\\CAWF\fP, the MS\-DOS environment
default;
or
.IR /usr/lib/cawf ,
the UNIX environment default.
These defaults can be overridden by the CAWFLIB environment variable,
or changed in the cawflib.h header file.

.ta \w'device.cf'u+3n
.nf
common	common device-independent initialization
device.cf	output device configurations
*.dev	device-specific initialization
m*.mac	macro package files
.SH DIAGNOSTICS
Unlike
.IR nroff ,
.I cawf
complains whenever it sees unknown requests.
All diagnostics appear on the standard error file.
.ad
.SH HISTORY
Vic Abell of Purdue University <[e-mail]> derived
.I cawf
from
.IR awf ,
\&``the Amazingly Workable (text) Formatter,'' 
written by Henry Spencer of the University of Toronto.
The Toronto work was a supplement to the C News project.
The Purdue effort was aimed at producing a C language version that
would run on small systems, particularly MS\-DOS ones.
The adaptation of the
.B me
macros was done by Chet Creider <[e-mail]>.
Chet also contributed ideas for device, font and type face support.
.PP
The MS\-DOS version of
.I cawf
has been compiled with version 2.5 of Microsoft's Quick-C compiler.
It runs under the Mortis Kern Systems Toolkit KornShell,
.IR ksh (1),
and COMMAND.COM.
.SH BUGS
Nroff and troff mavens will have many complaints.
Some may even represent bugs and not deliberate omissions.
.PP
Watch out for scaling factors - especially on requests like
.BR \ew .
.PP
The overprinting required to create bold and italicized characters is
tiresome on a slow printer.
The
.IR bsfilt (1)
post\-filter from this distribution may be used to alleviate that
nuisance by managing the backspacing codes from
.IR cawf 's
NORMAL device output.
.PP
The printing of bold and italic characters is sometimes better handled by
special printer codes.
Use
.IR cawf 's
.B \-c
.IR config ,
.BI \-d device
and
.BI \-f font
options to produce special font and device output control codes.
.PP
.I Cawf
has a small amount of built-in code for the 
.BR man ,
.B me
and
.B ms
macro packages, but none for any others.
.PP
The stacking for the
.B .so
request is limited.
.SH SEE ALSO
bsfilt(1),
colcrt(1),
man(7),
me(7),
ms(7)
and
nroff(1).