When filling is enabled, input and output line breaks generally do not
correspond. The roff
language therefore distinguishes input and
output line continuation.
\RET
¶\RET
(a backslash immediately followed by a newline)
suppresses the effects of that newline in the input. The next input
line thus retains the classification of its predecessor as a control or
text line. \RET
is useful for managing line lengths in the
input during document maintenance; you can even break an input line in
the middle of a word, request invocation, macro call, or escape
sequence. Input line continuation is invisible to the formatter, with
two exceptions: the |
operator recognizes the new input line
(see Numeric Expressions), and the input line counter register
.c
increments.
\RET
is interpreted even in copy mode.84
.ll 50n .de I . ft I . nop \\$* . ft .. Our film class watched .I The Effect of Gamma Rays on Man-in-the-Moon Marigolds. \" whoops, the input line wrapped .br .I My own opus begins on line \n[.c] \ and ends on line \n[.c].
⇒ Our film class watched The Effect of Gamma Rays on ⇒ Man-in-the-Moon Marigolds. ⇒ My own opus begins on line 11 and ends on line 12.
\c
¶\n[.int]
¶\c
continues an output line. Nothing after it on the input line
is formatted. In contrast to \RET
, a line after \c
remains a new input line, so a control character is recognized at its
beginning. The visual results depend on whether filling is enabled; see
Manipulating Filling and Adjustment.
\c
is continued
with the text on the next input text line, without an intervening space.
This is a te\c st. ⇒ This is a test.
\c
is
handled as a continuation of the same input text line.
.nf This is a \c test. ⇒ This is a test.
An intervening control line that causes a break overrides \c
,
flushing out the pending output line in the usual way.
The .int
register interpolates a positive value only if the
pending output line has been continued with \c
; this datum is
associated with the environment
(see Environments).85