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unix v7是最后一个广泛发布的研究型UNIX版本

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.tl 'May 15, 1977'''
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Summary of Changes to N/TROFF Since October 1976 Manual
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.ta \niu
.in \niu
.h Options
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-h	(Nroff only) Output tabs used during horizontal spacing
to speed output as well as reduce output byte count.
Device tab settings assumed to be every
8 nominal character widths.
The default settings of input (logical) tabs is also
initialized to every 8 nominal character widths.
.pp
-z	Efficiently suppresses formatted output.
Only message output will occur (from "tm"s and diagnostics).
.h "Old Requests"
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\&.ad\ c	The adjustment type indicator "c" may now also be a number
previously obtained from the ".j" register (see below).
.pp
\&.so\ name	The contents of file "name" will be interpolated
at the point the "so" is encountered.
Previously, the interpolation was done upon return to the file-reading input level.
.h "New Request"
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\&.ab\ text	\
Prints "text" on the message output and terminates
without further processing.
If "text" is missing, "User Abort." is printed.
Does not cause a break.
The output buffer is flushed.
.pp
\&.fz F N	\
forces f_ont "F" to be in siz_e N.
N may have the form N, +N, or -N.
For example,
     .fz 3 -2
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will cause an implicit \es-2 every time font 3 is entered,
and a corresponding \es+2 when it is left.
Special font characters occurring during the
reign of font F will have the same size modification.
If special characters are to be treated differently,
     .fz S F N
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may be used to specify the size treatment of special
characters during font F.
For example,
     .fz 3 -3
     .fz S 3 -0
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will cause automatic reduction of font 3 by 3 points
while the special characters would not be affected.
Any ``.fp'' request specifying a font on some position
must precede ``.fz'' requests relating to that position.
.h "New Predefined Number Registers."
.pp
\&.k	Read-only. Contains the horizontal size
of the text portion (without indent) of the current
partially collected output line, if any, in
the current environment.
.pp
\&.j	Read-only. A number representing the current adjustment mode and type.
Can be saved and later given to the "ad" request to restore a previous mode.
.pp
\&.P	Read-only.
1 if the current page is being printed,
and zero otherwise.
.pp
\&.L	Read-only.
Contains the current line-spacing parameter ("ls").
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\&c.	General register access to the input line-number
in the current input file.
Contains the same value as the read-only ".c" register.