Minimal cleanup of the COMPATIBILITY section:

* Mention that the list is incomplete.
* Quoting quotes by doubling them is documented in the
Ossanna/Kernighan/Ritter Nroff/Troff User's Manual, Section 7.3.
* Our roff(7) manual documents handling of escape sequences;
besides, we partially support \w and \z now.
* Scaling widths are documented in roff(7) as well, and f is not \f.
* Negative arguments to .sp are handled now.

1 files changed, 9 insertions, 38 deletions

diff --git a/man.7 b/man.7
index e72c27a7..496f9911 100644
--- a/man.7
+++ b/man.7
@@ -873,10 +873,11 @@ Note that macros like
 .Sx \&BR
 open and close a font scope for each argument.
 .Sh COMPATIBILITY
-This section documents areas of questionable portability between
+This section mentions some areas of questionable portability between
 implementations of the
 .Nm
 language.
+More incompatibilities exist.
 .Pp
 .Bl -dash -compact
 .It
@@ -888,47 +889,12 @@ to close out a literal context opened with
 .Sx \&nf .
 This behaviour may not be portable.
 .It
-In quoted literals, GNU troff allowed pair-wise double-quotes to produce
-a standalone double-quote in formatted output.
-It is not known whether this behaviour is exhibited by other formatters.
-.It
 troff suppresses a newline before
 .Sq \(aq
 macro output; in mandoc, it is an alias for the standard
 .Sq \&.
 control character.
 .It
-The
-.Sq \eh
-.Pq horizontal position ,
-.Sq \ev
-.Pq vertical position ,
-.Sq \em
-.Pq text colour ,
-.Sq \eM
-.Pq text filling colour ,
-.Sq \ez
-.Pq zero-length character ,
-.Sq \ew
-.Pq string length ,
-.Sq \ek
-.Pq horizontal position marker ,
-.Sq \eo
-.Pq text overstrike ,
-and
-.Sq \es
-.Pq text size
-escape sequences are all discarded in mandoc.
-.It
-The
-.Sq \ef
-scaling unit is accepted by mandoc, but rendered as the default unit.
-.It
-The
-.Sx \&sp
-macro does not accept negative values in mandoc.
-In GNU troff, this would result in strange behaviour.
-.It
 In page header lines, GNU troff versions up to and including 1.21
 only print
 .Ar volume
@@ -944,8 +910,13 @@ is given, like in
 .El
 .Pp
 The
-.Sx OP
-macro is part of the extended
+.Sx EE ,
+.Sx EX ,
+.Sx OP ,
+.Sx UE ,
+and
+.Sx UR
+macros are part of the GNU extended
 .Nm
 macro set, and may not be portable to non-GNU troff implementations.
 .Sh SEE ALSO