[groff] 08/16: doc/groff.texi: Resync with doc/ms.ms.

[G. Branden Robinson]

gbranden pushed a commit to branch master
in repository groff.

commit a4d23d4c2821567731c32abb1b17845e29fbf51c
Author: G. Branden Robinson <g.branden.robinson@gmail.com>
AuthorDate: Wed Dec 14 15:08:11 2022 -0600

    doc/groff.texi: Resync with doc/ms.ms.
---
 doc/groff.texi | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/doc/groff.texi b/doc/groff.texi
index b7e8dda94..920a4bd7e 100644
--- a/doc/groff.texi
+++ b/doc/groff.texi
@@ -3250,10 +3250,15 @@ available, differing in how indentation applies to 
them: to left, right,
 or both margins; to the first output line of the paragraph, all output
 lines, or all but the first.  All paragraphing macro calls cause the
 insertion of vertical space in the amount stored in the @code{PD}
-register, except at page or column breaks.  The @code{PORPHANS} register
-(@pxref{ms Document Control Settings}) operates in conjunction with each
-of these macros to inhibit the printing of isolated lines at the bottom
-of any page.
+register, except at page or column breaks.
+
+The @code{PORPHANS} register defines the minimum number of initial lines
+of any paragraph that must be kept together to avoid isolated lines at
+the bottom of a page.  If a new paragraph is started close to the bottom
+of a page, and there is insufficient space to accommodate
+@samp{\[rs]n[PORPHANS]} lines before an automatic page break, then a
+page break is forced before the start of the paragraph.  This is a GNU
+extension.
 
 @Defmac {LP, , ms}
 Set a paragraph without any (additional) indentation.