The commands in this subsection have a command code consisting of a single character, taking a fixed number of arguments. Most of them are commands for positioning and text writing. These commands are tolerant of whitespace. Optionally, syntactical space can be inserted before, after, and between the command letter and its arguments. All of these commands are stackable; i.e., they can be preceded by other simple commands or followed by arbitrary other commands on the same line. A separating syntactical space is necessary only when two integer arguments would clash or if the preceding argument ends with a string argument.
C id‹whitespace›Typeset the glyph of the special character id. Trailing syntactical space is necessary to allow special character names of arbitrary length. The drawing position is not advanced.
c gTypeset the glyph of the ordinary character c. The drawing position is not advanced.
f nSelect the font mounted at position n. n cannot be negative.
H nHorizontally move the drawing position to n basic units from the left edge of the page. n cannot be negative.
h nMove the drawing position right n basic units. AT&T
troff allowed negative n; GNU troff does not produce
such values, but groff’s output driver library handles them.
m color-scheme [component …]Select the stroke color using the components in the color space
scheme. Each component is an integer between 0 and 65535.
The quantity of components and their meanings vary with each
scheme. This command is a groff extension.
mc cyan magenta yellowUse the CMY color scheme with components cyan, magenta, and yellow.
mdUse the default color (no components; black in most cases).
mg grayUse a grayscale color scheme with a component ranging between 0 (black) and 65535 (white).
mk cyan magenta yellow blackUse the CMYK color scheme with components cyan, magenta, yellow, and black.
mr red green blueUse the RGB color scheme with components red, green, and blue.
N nTypeset the glyph with index n in the current font.
n is normally a non-negative integer. The drawing position
is not advanced. The html and xhtml devices use this
command with negative n to produce unbreakable space; the
absolute value of n is taken and interpreted in basic units.
n b aIndicate a break. No action is performed; the command is present to
make the output more easily parsed. The integers b
and a describe the vertical space amounts before and after
the break, respectively. GNU troff issues this command but
groff’s output driver library ignores it. See v and
V below.
p nBegin a new page, setting its number to n. Each page is
independent, even from those using the same number. The vertical
drawing position is set to 0. All positioning, writing, and
drawing commands are interpreted in the context of a page, so a
p command must precede them.
s nSet type size to n scaled points (unit z in GNU
troff.
AT&T troff used unscaled points p instead;
see Output Language Compatibility.
t xyz‹whitespace›t xyz dummy-arg‹whitespace›Typeset a word xyz; that is, set a sequence of ordinary glyphs
named x, y, z, …, terminated by a space
character or a line break; an optional second integer argument is
ignored (this allows the formatter to generate an even number of
arguments). Each glyph is set at the current drawing position, and the position is
then advanced horizontally by the glyph’s width. A glyph’s width is
read from its metrics in the font description file, scaled to the
current type size, and rounded to a multiple of the horizontal motion
quantum. Use the C command to emplace glyphs of special
characters. The t command is a groff extension and
is output only for devices whose DESC file contains the
tcommand directive; see DESC File Format.
u n xyz‹whitespace›Typeset word xyz with track kerning. As t, but after
placing each glyph, the drawing position is further advanced
horizontally by n basic units (u). The
u command is a groff extension and is output only for
devices whose DESC file contains the tcommand directive;
see DESC File Format.
V nVertically move the drawing position to n basic units from the top edge of the page. n cannot be negative.
v nMove the drawing position down n basic units. AT&T
troff allowed negative n; GNU troff does not produce
such values, but groff’s output driver library handles them.
wIndicate an inter-word space. No action is performed; the command is
present to make the output more easily parsed. Only adjustable,
breakable inter-word spaces are thus described; those resulting from
\~ or horizontal motion escape sequences are not. GNU
troff issues this command but groff’s output driver
library ignores it. See h and H above.