.;	RUNOFF Chapter 5
.;
.;	H.R. Tumblin 7-Jan-78
.;
.CH;Source File Format
.in RNOCHAINI
.ix Source File Format
.pp
The source file contains the textual material
which will appear on the final copy, plus information to
specify formatting.  Most importantly, upper and lower case
information also may be supplied so that material can be prepared on
the terminal or other such device which can normally input only
upper case letters.  All command information consists
of regular <ascii printing characters so that a listing of
the source file may be examined if the final copy is not
exactly as desired.
.pp
All material in the source file is taken to be source text
except those lines beginning with a period(.).  A line beginning
with a period is assumed to be a command, and must match one
of those listed.
The commands provide the formatting
information, and control various optional modes of operation.
.pp
Usually the text is filled
.ix Filling of text
and justified
.ix Justification of text
as it is processed.
That is, the program <fills a line by adding successive words
from the source text until one more word would cause the right
margin to be exceeded.  The line is then <justified by
making the word spacings larger until the last word in the line
exactly meets the right margin.
.PP
Formatting of a line with characters from a following line can be
prevented by creating what is called a "break". A "break" is caused
explicitly by the use of the break command, or it can be caused
implicitly by any of the commands that cause normal line spacing
to be interrupted. Breaking capabilities of each command can be found
in its complete description in the remainder of this manual.
.index Breaking Capabilities of Commands
.p
The user may occasionally wish to reproduce the source text
.ix Literals
exactly, which is done by
disabling filling and justification or by use of the <literal
command. The program may be set
to fill but not justify, in which case the output will be
normal except that lines will not be justified to the right margin.
The program may also be set to justify but not fill,
although this would probably produce peculiar results and
is not recommended.
.pp
When the fill mode is on, spaces, tabs,
.ix Space
.IX Word spacing
and carriage returns
occurring in the source text are treated only as word
separators.  Multiple separators are ignored.
.tp 5.s
The program will advance to new pages as necessary, placing
.ix Page Numbering
.ix TITLE
the title (if given) and the page number at the top of each
page, unless page numbering at the bottom of the page has
been enabled.  The user may call explicitly for a page advance where
desired, and may inhibit the occurrence of a page advance
within specified material.
.hl 1 Case Information
.ix Case Information
.p
If the text is prepared on a terminal with upper and lower case input
capability (VT52 or VT100 etc.), the following discussion of case shifting
may be ignored. Case shifting using %^%^ and %\%\ are needed only on terminals
which allow only uppercase characters.
.PP
Specification of case(1) for files prepared on the terminal is
done with two characters, circumflex
(%^, 136 octal), and back-slash (%\, 134 octal).
The appearance of a circumflex causes the letter immediately
following to be transmitted in upper case.  The appearance
of a back-slash causes the letter immediately following to
be converted to lower case.  Any letter not preceded by one of
these characters is transmitted in the current mode.  The mode
is initially upper case, and is changed by the occurrence
of two successive case control characters.  Two
circumflexes (%^%^) cause the mode to be set to upper case,
and two back-slashes (%\%\) cause the mode to be set to
lower case.
.S
.FN 10
_______________
.br
.;
.lm+3.i-3
(1)Case conversion takes place only on <ascii
codes 101 to 132 octal, that is, the upper case letters.  Any
actual lower case letters (codes 141 to 172 octal) appearing
in the source will be transmitted unchanged.
If the source is prepared by a terminal that has lowercase support,
then the mode should be set to uppercase at the beginning of
the file and left unchanged for the remainder.
.lm-3
!
The use of the above corresponds to the use of the shift and
shift-lock keys on a typewriter.  Usually, typing appears
in lower case. To type one letter in upper case, the shift
key is used.  The shift-lock is set to type a series of
upper case letters, after which it is released.
.S
The following shows the uses of the case control characters:
.S
%^HERE IS A %^SAMPLE %^SENTENCE IN %^%^UPPER CASE%\%\ AND LOWER CASE.
.S
becomes:
.S
Here is a Sample Sentence in <upper <case and lower case.
.S
.;
.pp
An additional character, less-than (%<, 074 octal), capitalizes
the entire word it precedes. It then returns the file to the
current case.  This character is not engaged unless preceded by
the <flags <capitalize command.
.ix %<
Similarly, the <flags <hyphenate command engages the special
.ix Hyphenation
character equals (%=, 075 octal), which causes hyphenation to be suspended
for the word it precedes.
!
.ix %=
.hl 1 Special Characters
.ix Special characters
.;
.hl 2 Underscoring
%&##Ampersand#####Underscoring
.pp
The character ampersand (%&, 046 octal) is used to specify
underscoring.
.ix Underscoring
.IX %&
The ampersand will cause the character following it to be
underscored (e.g. %&f%&o%&o becomes ^&foo\&).
.pp
Underlining of a string of characters can also be specified,
similar to the use of the shift lock operations described above.
An appearance of ampersand preceded by circumflex (%^%&) will
cause underlining of all following characters except space. An
appearance of ampersand preceded by backslash (%\%&) will
disable this mode.
.;
.hl2 Overbar
.ix Overbar
.ix %$
%$##Dollar Sign####Overbar indicator
.p
The character dollar sign (%$, 044 octal) is used to specify that the
character(s) following the dollar sign should have a line above them. This
is a very useful feature in preparing technical documents. Note however
that it will only function properly on a DIABLO type printer, and it's use
on other printers not supporting reverse linefeeds is unpredictable. There is
no alternative as there is with underlining. The underscore character is used
to create the overbar. The overbar will automatically adjust to accomodate the
highest (as in the case of overbarred superscripted expressions) character.
Circumflex and backslash lock on or off the overbar function.
.b
.ce;example:##### %^%$u'v'%\%$ becomes ^$u'v'\$.
.hl 2 Quoted Space
%###Number sign####Explicit or Quoted Space
.ix Quoted Space
.ix Explicit Space
.IX %#
.pp
It is occasionally necessary to include spaces in the text
which should not be treated as word separators. For
this purpose, <runoff treats the number-sign character (%#, 043 octal) as a
quoted space; i.e. it will print as exactly one space in the
output, and will never be expanded nor changed to a carriage return.
.b.lm+7.i-7
Note#-#In equation mode (between .EQ and .EEQ's) the number sign is
.ix Equation mode
interpreted to be one horizontal half-space. This allows centering of
expressions like 1/ab for example.
.lm-7
.;
.hl 2 Quote next character.
.ix %>
##>####Greater than##Quote next character
.PP
To allow the appearance of the special characters (ampersand(%&),
dollar sign(%$),
number sign(%#), circumflex(%^), backslash(%\), greater than(%>),
less than(%<), equals sign(%=),
at sign(%@), tilda(%~), percent sign (%%) or exclamation mark (%!)
in the output, the greater than character(>) is used as the
quote character. That is, the character immediately following a
greater than will be transmitted to the output file with no
formatting effect. Thus the following cases occur:
.ls
.le;>%&
.le;>%$
.le;>%#
.le;>%^
.le;>%\
.le;>>
.le;>%<
.le;>%=
.le;>%@
.le;>%~
.le;>%%
.le;>%!
.els
.ix Quote Next Character
.;
.hl 2 Upper case shift or mode lock.
##%^####Circumflex####Upper case shift or mode lock.
.pp
As described in section 5.1, the circumflex character(%^) is
used to convert the letter following to upper case. It is
also used to lock the case mode in upper case.
It is usually used in conjuntion with one of the special characters to
lock into the mode designated by the special character. e.g, to lock on
underlining or overbaring, lock on super/sub scipt, or to lock on selection
of the 2nd character set (usually greek).
.ix Upper Case Shift
.ix Mode Lock
.ix %^
.;
.tp 6
.hl 2 Lower case shift or mode unlock.
##%\####Backslash####Lower case shift or mode unlock
.pp
As described in section 5.1, the backslash character(%\) is used to
output the letter following in lower case. It is also used to
lock the case mode in lower case. It unlocks the mode locked into as described
in the above section.
.ix Lower Case Shift
.ix Mode Unlock
.ix %\
.;
.hl 2 Flags Capitalize.
##%<####Less than character####Capitalize entire word.
.pp
If the command "FLAGS-CAPITALIZE" has been engaged, then all
words preceded with a less than character(%<) will be capitalized.
If it is to be used in printed text, then it also must be
preceded by the quote character.
.ix Flags Capitalize
.ix %<
.;
.hl 2 Flags Hyphenate.
.ix %=
##%=####Equals sign####Hyphenation disable.
.pp
If the command "FLAGS-HYPHENATE" has been engaged, the equals
character(=) is used to disable hyphenation for the word
it precedes. If it is to appear in the printed text, then it
must be preceded by the quote character.
.ix Flags Hyphenate.
.;
.hl 2 Superscripting
##%@####at sign########Superscripting character
.pp
The at sign causes the next character to be placed a fraction of a line above the
line being typed for a superscript.  This character works only if the DI
switch is enabled.  Otherwise, the character is ignored.
The amount of superscript, or subscript, movement can be adjusted by the .SETSS
command and nesting of the at sign (%@). e.g., if super/subscipt movement is set
to 1/8 line, then x%@2 will raise the '2' 1/8 line above the 'x'. If we have
x%@%@%@2 then the '2' will be 3/8 of a line above the 'x'. This allows for very
fine adjustment of super/sub scripts within the text to allow for single
spacing and the use of subs and supers. The default movement value is 1/2 line.
Movement can be set to 1/8, 1/4, 3/8 or 1/2, see also .SETSS.
.ix Superscript
.ix %@
.;
.hl 2Subscripting
##%~####tilda##########Subscripting character
.pp
The %~ character causes the next character to be placed a fraction of a line below
the line being typed for a subscript.  This character works only if the DI
switch is enabled.  Otherwise, the character is ignored.
Refer to the above section on superscripting for a discussion of amount of
movement a subscript will have relative to the line.
.ix Subscript
.ix %~
.;
.hl 2Greek Processing
##%%####percent sign###Select 2nd character set
.p
.ix Greek processing
.ix %%
.ix Multiple Character sets
The %% character indicates to RUNOFF that the next character should be printed
from an alternate character set.
At arap we generally use this feature for printing greek characters used in
equations and technical documents. The %% mode can be locked and unlocked, like
underline, overbar etc., by use of the circumflex and backslash. The action
taken by RUNOFF when the %% is encountered is determined by the /CS switch on
the command line. We use a single wheel DIABLO 1640, so we make two passes at
the document. The first pass (/CS:1) will print all english text, select print
wheel 1. After rewinding the paper to the beginning of the document we repeat
the exact RUNOFF command line but use /CS:2, which will print only the
text marked by the %% sign character. Pass 1 leaves the appropriate spaces
for pass 2 printing. This method has worked very well for us at arap, and
we do quite a lot of complex equations and greek. Obviously, a QUME twin-track
printer would be the ideal solution. Modifying RUNOFF to work with QUME escape
sequences would probably be straightforward.
.hl 2Backspace/Overstrike
.ix Backspace character
.ix %^H
.ix Overstrike
##%^H####control H#######Backspace character
.p
A backspace facility is essential in scientific text processing. Many times
one needs both a super and a subscipt at the same location.
.b.NJ
.ce;example:####x'%^H%~2##becomes x'~2##or e%^H%^##becomes##e%^.
.b.J
The backspace works properly when a line is justified.
.hl 2In-line comments
##%!####exclamation mark#In-line comments/remarks
.p
The exclamation mark, unless preceded by 'quote next character', indicates to
RUNOFF that the text following should be ignored. Note also that %! works as
.ix %!
.ix Comments
.ix Equation mode
an on/off switch. That is, if a second %! appears, the commenting is turned
off and the remaining text is processed by RUNOFF. This feature is used in
setting up a template file for creating equations using the .EQ command.
.hl 1 Special Characters - Notes
.ls
.le;Nesting of special characters
Special characters may be combined in any fashion and may appear next to each
other. A typical example is a super/subscipt greek character. The %% should
precede the character it is to modify. e.g. x%@%%a would result in x super
alpha. Note that the greek input should be the same character you would type
.ix Greek processing
in an IBM selectric typewriter using the SYMBOL 10 print ball. RUNOFF makes ther
proper translation of this input to be compatible with the QUME scientific print
wheel.
.els
.; End of chapter 5