Implement the roff(7) .nop (no operation) request.

Examples of manual pages (ab)using it
include groff(7), chem(1), groff_mom(7), and groff_hdtbl(7).

1 files changed, 7 insertions, 4 deletions

diff --git a/roff.7 b/roff.7
index b7f499d9..f7036ef4 100644
--- a/roff.7
+++ b/roff.7
@@ -206,7 +206,7 @@ Unescaped trailing spaces are stripped from text line input unless in a
 literal context.
 In general, trailing whitespace on any input line is discouraged for
 reasons of portability.
-In the rare case that a blank character is needed at the end of an
+In the rare case that a space character is needed at the end of an
 input line, it may be forced by
 .Sq \e\ \e& .
 .Pp
@@ -665,7 +665,7 @@ produces
 .Pp
 in the input stream, and thus in the output: \fI\^XtFree\^\fP.
 Each occurrence of \e\e$* is replaced with all the arguments,
-joined together with single blank characters.
+joined together with single space characters.
 .Pp
 Since macros and user-defined strings share a common string table,
 defining a macro
@@ -1346,8 +1346,11 @@ Currently unsupported.
 Temporarily turn off line numbering.
 Currently unsupported.
 .It Ic \&nop Ar body
-Execute the rest of the input line as a request or macro line.
-Currently unsupported.
+Execute the rest of the input line as a request, macro, or text line,
+skipping the
+.Ic \&nop
+request and any space characters immediately following it.
+This is mostly used to indent text lines inside macro definitions.
 .It Ic \&nr Ar register Oo Cm + Ns | Ns Cm - Oc Ns Ar expression Op Ar stepsize
 Define or change a register.
 A register is an arbitrary string value that defines some sort of state,