* src/roff/troff/input.cc (pipe_output): Multiple calls to `pi'

will now form a chain, e.g.

  .pi foo
  .pi bar

is now the same as

  .pi foo | bar

This is for compatibility with plan 9's troff.

* tmac/tty.tmac: Set default tab values to 0.8i to be compatible
with UNIX troff.
* NEWS: Updated.

* doc/groff.texinfo: Add documentation of remaining requests and
registers.

1 files changed, 13 insertions, 0 deletions

diff --git a/NEWS b/NEWS
index a1b5ec5f..c43e9cb3 100644
--- a/NEWS
+++ b/NEWS
@@ -132,12 +132,25 @@ o The request `pvs' isn't new, but hasn't been documented before.  It
   The read-only register `.pvs' holds the current amount of the
   post-vertical line space.
 
+o For compatibility with plan 9's troff, multiple `pi' requests are
+  supported:
+
+    .pi foo
+    .pi bar
+
+  is now equivalent to
+
+    .pi foo | bar
+
 o A new escape sequence `\O' is available (mainly for internal use with
   grohtml).  Please see groff_diff.7 and groff.texinfo for more details.
 
 o The escapes `\%', `\&', `\)', and `\:' no longer cause an error in \X;
   they are ignored now.
 
+o The default tab distance in nroff mode is now 0.8i to be compatible
+  with UNIX troff.
+
 o Using the latin-1 input character 0xAD (soft hyphen) for the `shc'
   request was a bad idea.  Instead, it is now translated to `\%', and
   the default hyphenation character is again \[hy].  Note that the glyph