522 lines
18 KiB
Plaintext
522 lines
18 KiB
Plaintext
.\" Copyright (C) Caldera International Inc. 2001-2002. All rights reserved.
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.\"
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.\" Redistribution and use in source and binary forms, with or without
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.\" modification, are permitted provided that the following conditions are
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.\" met:
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.\"
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.\" Redistributions of source code and documentation must retain the above
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.\" copyright notice, this list of conditions and the following
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.\" disclaimer.
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.\"
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.\" Redistributions in binary form must reproduce the above copyright
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.\" notice, this list of conditions and the following disclaimer in the
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.\" documentation and/or other materials provided with the distribution.
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.\"
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.\" All advertising materials mentioning features or use of this software
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.\" must display the following acknowledgement:
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.\"
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.\" This product includes software developed or owned by Caldera
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.\" International, Inc. Neither the name of Caldera International, Inc.
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.\" nor the names of other contributors may be used to endorse or promote
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.\" products derived from this software without specific prior written
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.\" permission.
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.\"
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.\" USE OF THE SOFTWARE PROVIDED FOR UNDER THIS LICENSE BY CALDERA
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.\" INTERNATIONAL, INC. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR
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.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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.\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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.\" DISCLAIMED. IN NO EVENT SHALL CALDERA INTERNATIONAL, INC. BE LIABLE
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.\" FOR ANY DIRECT, INDIRECT INCIDENTAL, SPECIAL, EXEMPLARY, OR
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.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
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.\" BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
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.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
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.\" OR OTHERWISE) RISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
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.\" IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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.\"
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.\" @(#)m3 8.1 (Berkeley) 8/14/93
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.\"
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.\" $FreeBSD$
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.tr |
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.rm mx
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.mh
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Tabs, Leaders, and Fields
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.sc
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Tabs and leaders.
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The \s-1ASCII\s+1 horizontal tab character and the \s-1ASCII\s+1
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\s-1SOH\s+1 (hereafter known as the \fIleader\fR character)
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can both be used to generate either horizontal motion or
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a string of repeated characters.
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The length of the generated entity is governed
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by internal \fItab stops\fR specifiable
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with \fBta\fR.
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The default difference is that tabs generate motion and leaders generate
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a string of periods;
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\fBtc\fR and \fBlc\fR
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offer the choice of repeated character or motion.
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There are three types of internal tab stops\(em\
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\fIleft\fR adjusting, \fIright\fR adjusting,
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and \fIcentering\fR.
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In the following table:
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\fID\fR is the distance from the current position on the \fIinput\fR line
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(where a tab or leader was found)
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to the next tab stop;
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\fInext-string\fR consists
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of the input characters following the tab (or leader) up to the next tab (or leader) or end of line;
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and
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\fIW\fR is the width of \fInext-string\fR.
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.TS
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center box;
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c2|c2|c
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c2|c2|c
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c2|c2|l.
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Tab Length of motion or Location of
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type repeated characters \fInext-string\fR
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_
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Left \fID\fR Following \fID\fR
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Right \fID\-W\fR Right adjusted within \fID\fR
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Centered \fID\-W\(sl\fR2 Centered on right end of \fID\fR
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.TE
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The length of generated motion is allowed to be negative, but
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that of a repeated character string cannot be.
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Repeated character strings contain an integer number of characters, and
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any residual distance is prepended as motion.
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Tabs or leaders found after the last tab stop are ignored, but may be used
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as \fInext-string\fR terminators.
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.pg
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Tabs and leaders are not interpreted in \fIcopy mode\fR.
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\fB\et\fR and \fB\ea\fR always generate a non-interpreted
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tab and leader respectively, and
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are equivalent to actual tabs and leaders in \fIcopy mode\fR.
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.sc
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Fields.
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A \fIfield\fR is contained between
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a \fIpair\fR of \fIfield delimiter\fR characters,
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and consists of sub-strings
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separated by \fIpadding\fR indicator characters.
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The field length is the distance on the
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\fIinput\fR line from the position where the field begins to the next tab stop.
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The difference between the total length of all the sub-strings
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and the field length is incorporated as horizontal
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padding space that is divided among the indicated
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padding places.
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The incorporated padding is allowed to be negative.
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For example,
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if the field delimiter is \fB#\fR and the padding indicator is \fB^\fR,
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\fB#^\fIxxx\fB^\fIright\|\fB#\fR
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specifies a right-adjusted string with the string \fIxxx\fR centered
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in the remaining space.
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.h1
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.bt
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\fB&ta\fI|Nt|...\fR 8n;|0.5in none E,\fBm\fR \
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Set tab stops and types.
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\fIt=\fBR\fR, right adjusting;
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\fIt=\fBC\fR, centering;
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\fIt\fR absent, left adjusting.
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\*(TR tab stops are preset every 0.5in.;
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\*(NR every 8 character widths.
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The stop values are separated by spaces, and
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a value preceded by \fB+\fR
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is treated as an increment to the previous stop value.
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.bt
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\fB&tc\fI|c\fR none none E \
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The tab repetition character becomes \fIc\fR,
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or is removed specifying motion.
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.bt
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\fB&lc\fI|c\fR \fB.\fR none E \
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The leader repetition character becomes \fIc\fR,
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or is removed specifying motion.
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.bt
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\fB&fc\fI|a|b\fR off off - \
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The field delimiter is set to \fIa\fR;
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the padding indicator is set to the \fIspace\fR character or to
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\fIb\fR, if given.
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In the absence of arguments the field mechanism is turned off.
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.mh
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Input and Output Conventions and Character Translations
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.sc
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Input character translations.
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Ways of inputting the graphic character set were
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discussed in \(sc2.1.
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The \s-1ASCII\s+1 control characters horizontal tab (\(sc9.1),
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\s-1SOH\s+1 (\(sc9.1), and backspace (\(sc10.3) are discussed elsewhere.
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The newline delimits input lines.
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In addition,
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\s-1STX\s+1, \s-1ETX\s+1, \s-1ENQ\s+1, \s-1ACK\s+1, and \s-1BEL\s+1
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are accepted,
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and may be used as delimiters or translated into a graphic with \fBtr\fR (\(sc10.5).
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\fIAll\fR others are ignored.
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.pg
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The \fIescape\fR character \fB\e\fR
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introduces \fIescape sequences\fR\(em\
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causes the following character to mean
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another character, or to indicate
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some function.
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A complete list of such sequences is given in the Summary and Index on page 6.
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\fB\e\fR
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should not be confused with the \s-1ASCII\s+1 control character \s-1ESC\s+1 of the
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same name.
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The escape character \fB\e\fR can be input with the sequence \fB\e\e\fR.
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The escape character can be changed with \fBec\fR,
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and all that has been said about the default \fB\e\fR becomes true
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for the new escape character.
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\fB\ee\fR can be used to print whatever the current escape character is.
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If necessary or convenient, the escape mechanism may be turned off with \fBeo\fR,
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and restored with \fBec\fR.
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.h1
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.bt
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\fB&ec\fI|c\fR \fB\e\fR \fB\e\fR - \
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Set escape character to \fB\e\fR, or to \fIc\fR, if given.
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.bt
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\fB&eo\fR on - - Turn escape mechanism off.
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.sc
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Ligatures.
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.lg 0
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Five ligatures are available
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in the current \*(TR character set \(em
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\fB\(fi\fR, \fB\(fl\fR, \fB\(ff\fR, \fB\(Fi\fR, and \fB\(Fl\fR.
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They may be input (even in \*(NR) by
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\fB\e(fi\fR, \fB\e(fl\fR, \fB\e(ff\fR, \fB\e(Fi\fR, and \fB\e(Fl\fR respectively.
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.lg
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The ligature mode is normally on in \*(TR, and \fIautomatically\fR invokes
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ligatures during input.
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.h1
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.bt
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\fB&lg\fI|N\fR off;|on on - Ligature mode
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is turned on if \fIN\fR is absent or non-zero,
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and turned off if \fIN\(eq\^\fR0.
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If \fIN\fR\(eq\^2, only the two-character ligatures are automatically invoked.
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Ligature mode is inhibited for
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request, macro, string, register, or file names,
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and in \fIcopy mode\fR.
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No effect in \*(NR.
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.sc
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Backspacing, underlining, overstriking, etc.
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Unless in \fIcopy mode\fR, the \s-1ASCII\s+1 backspace character is replaced
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by a backward horizontal motion having the width of the
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space character.
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Underlining as a form of line-drawing is discussed in \(sc12.4.
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A generalized overstriking function is described in \(sc12.1.
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.pg
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\*(NR automatically underlines
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characters in the \fIunderline\fR font,
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specifiable with \fBuf\fR,
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normally Times Italic on font position 2 (see \(sc2.2).
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In addition to \fBft\fR and \fB\ef\fIF\fR,
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the underline font may be selected by \fBul\fR and \fBcu\fR.
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Underlining is restricted to an output-device-dependent
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subset of \fIreasonable\fR characters.
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.h1
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.bt
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\fB&ul\fI|N\fR off \fIN\(eq\fR1 E \
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Underline in \*(NR (italicize in \*(TR) the next \fIN\fR
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input text lines.
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Actually, switch to \fIunderline\fR font, saving the
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current font for later restoration;
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\fIother\fR font changes within the span of a \fBul\fR
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will take effect,
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but the restoration will undo the last change.
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Output generated by \fBtl\fR (\(sc14) \fIis\fR affected by the
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font change, but does \fInot\fR decrement \fIN\fR.
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If \fIN\fR\^>\^1, there is the risk that
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a trap interpolated macro may provide text
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lines within the span;
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environment switching can prevent this.
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.bt
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\fB&cu\fI|N\fR off \fIN\(eq\fR1 E \
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A variant of \fBul\fR that causes \fIevery\fR character to be underlined in \*(NR.
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Identical to \fBul\fR in \*(TR.
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.bt
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\fB&uf\fI|F\fR Italic Italic - \
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Underline font set to \fIF\fR.
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In \*(NR,
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\fIF\fR may \fInot\fR be on position 1 (initially Times Roman).
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.sc
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Control characters.
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Both the control character \fB.\fR and the \fIno-break\fR
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control character \fB\'\fR may be changed, if desired.
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Such a change must be compatible with the design
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of any macros used in the span of the change,
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and
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particularly of any trap-invoked macros.
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.h1
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.bt
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\fB&cc\fI|c\fR \fB.\fR \fB.\fR E \
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The basic control character is set to \fIc\fR,
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or reset to "\fB.\fR".
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.bt
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\fB&c2\fI|c\fR \fB\' \'\fR E The \fInobreak\fR control character is set
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to \fIc\fR, or reset to "\fB\'\fR".
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.sc
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Output translation.
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One character can be made a stand-in for another character using \fBtr\fR.
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All text processing (e. g. character comparisons) takes place
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with the input (stand-in) character which appears to have the width of the final
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character.
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The graphic translation occurs at the moment of output
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(including diversion).
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.h1
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.bt
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\fB&tr\fI|abcd....\fR none - O Translate \
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\fIa\fR into \fIb\fR, \fIc\fR into \fId\fR, etc.
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If an odd number of characters is given,
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the last one will be mapped into the space character.
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To be consistent, a particular translation
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must stay in effect from \fIinput\fR to \fIoutput\fR time.
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.sc
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Transparent throughput.
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An input line beginning with a \fB\e!\fR is read in \fIcopy mode\fR and \fItransparently\fR output
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(without the initial \fB\e!\fR);
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the text processor is otherwise unaware of the line's presence.
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This mechanism may be used to pass control information to a post-processor
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or to imbed control lines in a macro created by a diversion.
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.sc
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Comments and concealed newlines.
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An uncomfortably long input line that must stay
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one line (e. g. a string definition, or nofilled text)
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can be split into many physical lines by ending all but
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the last one with the escape \fB\e\fR.
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The sequence \fB\e\fR(newline) is \fIalways\fR ignored\(em\
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except in a comment.
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Comments may be imbedded at the \fIend\fR of any line by
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prefacing them with \fB\e"\fR.
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The newline at the end of a comment cannot be concealed.
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A line beginning with \fB\e"\fR will appear as a blank line and
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behave like \fB.sp|1\fR;
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a comment can be on a line by itself by beginning the line with \fB.\e"\fR.
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.mh
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Local Horizontal and Vertical Motions, and the Width Function
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.sc
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Local Motions.
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The functions \fB\ev\'\fIN\fB\|\'\fR and
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\fB\eh\'\fIN\fB\|\'\fR
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can be used for \fIlocal\fR vertical and horizontal motion respectively.
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The distance \fIN\fR may be negative; the \fIpositive\fR directions
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are \fIrightward\fR and \fIdownward\fR.
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A \fIlocal\fR motion is one contained \fIwithin\fR a line.
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To avoid unexpected vertical dislocations, it is necessary that
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the \fInet\fR vertical local motion within a word in filled text
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and otherwise within a line balance to zero.
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The above and certain other escape sequences providing local motion are
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summarized in the following table.
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.tr ||
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.ds X \0\0\0
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.TS
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center box;
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c2|cs2||c2|cs
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c1|c2c2||c2|c2c.
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Vertical Effect in Horizontal Effect in
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Local Motion \*(TR \*(NR Local Motion \*(TR \*(NR
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_
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.sp .4
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.T&
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l2|ls2||l2|ls.
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\fB\*X\ev\'\fIN\|\^\fB\'\fR Move distance \fIN\fR \
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\fB\*X\eh\'\fIN\|\^\fB\'\fR Move distance \fIN\fR
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.T&
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_2|_2_2||l2|ls.
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\fB\*X\e\fR(space) Unpaddable space-size space
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.T&
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l2|l2|l2||l2|ls.
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\fB\*X\eu\fR \(12 em up \(12 line up \fB\*X\e0\fR Digit-size space
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.T&
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l2|l2|l2||_2|_2_.
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\fB\*X\ed\fR \(12 em down \(12 line down
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.T&
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l2|l2|l2||l2|l2|l.
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\fB\*X\er\fR 1 em up 1 line up \fB\*X\e\||\fR 1\(sl6 em space ignored
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\fB\*X\e^\fR 1\(sl12 em space ignored
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.sp .4
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.TE
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.rm X
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.tr |
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As an example,
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\fBE\s-2\v'-.4m'2\v'.4m'\s+2\fR
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could be generated by the sequence
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\fBE\es\-2\ev\'\-0.4m\'2\ev\'0.4m\'\es+2\fR;
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it should be noted in this example that
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the 0.4|em vertical motions are at the smaller size.
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.sc
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Width Function.
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The \fIwidth\fR function \fB\ew\'\fIstring\fB\|\'\fR
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generates the numerical width of \fIstring\fR (in basic units).
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Size and font changes may be safely imbedded in \fIstring\fR,
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and will not affect the current environment.
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For example,
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\&\fB.ti|\-\\w\'1.|\'u\fR could be used to
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temporarily indent leftward a distance equal to the
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size of the string "\fB1.|\fR".
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.pg
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The width function also sets three number registers.
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The registers \fBst\fR and \fBsb\fR are set respectively to the highest and
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lowest extent of \fIstring\fR relative to the baseline;
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then, for example,
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the total \fIheight\fR of the string is \fB\en(stu\-\en(sbu\fR.
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In \*(TR the number register \fBct\fR is set to a value
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between 0|and|3:
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0 means that all of the characters in \fIstring\fR were short lower
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case characters without descenders (like \fBe\fR);
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1 means that at least one character has a descender (like \fBy\fR);
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2 means that at least one character is tall (like \fBH\fR);
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and 3 means that both tall characters and characters with
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descenders are present.
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.sc
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Mark horizontal place.
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The escape sequence \fB\ek\fIx\fR will cause the \fIcurrent\fR horizontal
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position in the \fIinput line\fR to be stored in register \fIx\fR.
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As an example,
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the construction \fB\ekx\fIword\|\fB\eh\'\|~\|\enxu+2u\'\fIword\fB\fR
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will embolden \fIword\fR by backing up to almost its beginning and overprinting it,
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resulting in \kz\fIword\fR\h'|\nzu+2u'\fIword\fR.
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.mh
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Overstrike, Bracket, Line-drawing, and Zero-width Functions
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.sc
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Overstriking.
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Automatically centered overstriking of up to nine characters
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is provided by the \fIoverstrike\fR function
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\fB\eo\'\fIstring\fB\|\'\fR.
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The characters in \fIstring\fR are overprinted with centers aligned; the total width
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is that of the widest character.
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\fIstring\fR should \fInot\fR contain local vertical motion.
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As examples,
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\fB\eo\'e\e\'\'\fR produces \fB\o'e\''\fR, and
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\fB\eo\'\e(mo\e(sl\'\fR produces \fB\o'\(mo\(sl'\fR.
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.sc
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Zero-width characters.
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The function \fB\ez\fIc\fR will output \fIc\fR without spacing over
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it, and can be used to produce left-aligned overstruck
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combinations.
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As examples,
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\fB\ez\e(ci\e(pl\fR will produce \fB\z\(ci\(pl\fR, and
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\fB\e(br\ez\e(rn\e(ul\e(br\fR will produce the smallest possible
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constructed box \fB\(br\z\(rn\(ul\(br\fR\|.
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.sc
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Large Brackets.
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The Special Mathematical Font contains a number of bracket construction pieces
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(\|\|\|\(lt\|\|\|\(lb\|\|\|\(rt\|\|\|\(rb\|\|\|\(lk\|\|\|\(rk\|\|\|\(bv\|\|\|\(lf\|\|\|\(rf\|\|\|\(lc\|\|\|\(rc\|\|)
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that can be combined into various bracket styles.
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The function \fB\eb\'\fIstring\fB\|\'\fR may be used to pile
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up vertically the characters in \fIstring\fR
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(the first character on top and the last at the bottom);
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the characters are vertically separated by 1|em and the total
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pile is centered 1\(sl2\|em above the current baseline
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(\(12 line in \*(NR).
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For example,
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\fB\eb\'\|\e(lc\e(lf\|\'E\e\|~\|\eb\'\|\e(rc\e(rf\|\'\|\ex\'\|\-0.5m\'\|\ex\'0.5m\'\|\fR
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produces
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\x'-.5m'\x'.5m'\fB\b'\(lc\(lf'E\|\b'\(rc\(rf'\fR.
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.sc
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Line drawing.
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.tr &&
|
|
The function \fB\e\|l\|\'\fINc\fB\|\'\fR will draw a string of repeated \fIc\fR\|'s towards the right for a distance \fIN\fR.
|
|
(\|\fB\el\fR is \fB\e\fR(lower case L).
|
|
If \fIc\fR looks like a continuation of
|
|
an expression for \fIN\fR, it may insulated from \fIN\fR with a \fB\e&\fR.
|
|
If \fIc\fR is not specified, the \fB\(ru\fR (baseline rule) is used
|
|
(underline character in \*(NR).
|
|
If \fIN\fR is negative, a backward horizontal motion
|
|
of size \fIN\fR is made \fIbefore\fR drawing the string.
|
|
Any space resulting from \fIN\fR\|\(sl(size of \fIc\fR) having a remainder is put at the beginning (left end)
|
|
of the string.
|
|
In the case of characters
|
|
that are designed to be connected such as
|
|
baseline-rule\ \fB\(ru\fR\|,
|
|
underrule\ \fB\(ul\fR\|,
|
|
and
|
|
root-en\ \fB\(rn\fR\|,
|
|
the remainder space is covered by over-lapping.
|
|
If \fIN\fR is \fIless\fR than the width of \fIc\fR,
|
|
a single \fIc\fR is centered on a distance \fIN\fR.
|
|
As an example, a macro to underscore a string can be written
|
|
.br
|
|
.tr &.
|
|
.x1
|
|
.ft B
|
|
.ne 2.1
|
|
&de us
|
|
\e\e$1\e\|l\|\'\|~\|0\e(ul\'
|
|
&&
|
|
.ft R
|
|
.x2
|
|
.ne 2.1
|
|
.de xu
|
|
\\$1\l'|0\(ul'
|
|
..
|
|
or one to draw a box around a string
|
|
.x1
|
|
.ft B
|
|
&de bx
|
|
\e(br\e\|~\|\e\e$1\e\|~\|\e(br\e\|l\|\'\|~\|0\e(rn\'\e\|l\|\'\|~\|0\e(ul\'
|
|
&&
|
|
.ft R
|
|
.x2
|
|
.de bx
|
|
\(br\|\\$1\|\(br\l'|0\(rn'\l'|0\(ul'
|
|
..
|
|
such that
|
|
.x1
|
|
.ft B
|
|
&us "underlined words"
|
|
.ft R
|
|
.x2
|
|
and
|
|
.x1
|
|
.ft B
|
|
&bx "words in a box"
|
|
.ft R
|
|
.x2
|
|
yield
|
|
.xu "underlined words"
|
|
and
|
|
.bx "words in a box"
|
|
\h'-\w'.'u'.
|
|
.pg
|
|
The function \fB\eL\'\|\fINc\fB\|\'\fR will draw a vertical line consisting
|
|
of the (optional) character \fIc\fR stacked vertically apart 1\|em
|
|
(1 line in \*(NR),
|
|
with the first two characters overlapped,
|
|
if necessary, to form a continuous line.
|
|
The default character is the \fIbox rule\fR |\(br| (\fB\|\e(br\fR);
|
|
the other suitable character is the \fIbold vertical\fR \|\(bv\| (\fB\|\e(bv\fR).
|
|
The line is begun without any initial motion relative to the
|
|
current base line.
|
|
A positive \fIN\fR specifies a line drawn downward and
|
|
a negative \fIN\fR specifies a line drawn upward.
|
|
After the line is drawn \fIno\fR compensating
|
|
motions are made;
|
|
the instantaneous baseline is at the \fIend\fR of the line.
|
|
.pg
|
|
.de eb
|
|
.sp -1
|
|
.nf
|
|
\h'-.5n'\L'|\\nzu-1'\l'\\n(.lu+1n\(ul'\L'-|\\nzu+1'\l'|0u-.5n\(ul'
|
|
.fi
|
|
..
|
|
.ne 2i
|
|
.mk z
|
|
The horizontal and vertical line drawing functions may be used
|
|
in combination to produce large boxes.
|
|
The zero-width \fIbox-rule\fR and the \(12-em wide \fIunderrule\fR
|
|
were \fIdesigned\fR to form corners when using 1-em vertical
|
|
spacings.
|
|
For example the macro
|
|
.x1
|
|
.ft B
|
|
\&.de eb
|
|
\&.sp \-1 \e"compensate for next automatic base-line spacing
|
|
\&.nf \e"avoid possibly overflowing word buffer
|
|
.tr ||
|
|
\&\eh\'\-.5n\'\eL\'\||\|\e\enau\-1\'\el\'\e\en(.lu+1n\e(ul\'\eL\'\-\||\|\e\enau+1\'\el\'\||\|0u\-.5n\e(ul\' \e"draw box
|
|
.tr |
|
|
.lg 0
|
|
\&.fi
|
|
.lg
|
|
\&..
|
|
.ft R
|
|
.x2
|
|
will draw a box around some text whose beginning vertical place was
|
|
saved in number register \fIa\fR
|
|
(e. g. using \fB.mk|a\fR)
|
|
as done for this paragraph.
|
|
.eb
|