Supplement the documentation of the .St macro by minimal commentary

regarding the content and relationships of the various standards,
and sort and group them.
tweaks and ok guenther@, ok millert@ sobrado@ jmc@

1 files changed, 201 insertions, 73 deletions

diff --git a/mdoc.7 b/mdoc.7
index 910e41a8..c47e520b 100644
--- a/mdoc.7
+++ b/mdoc.7
@@ -2354,115 +2354,243 @@ and
 .Sx \&Sx .
 .Ss \&St
 Replace an abbreviation for a standard with the full form.
-The following standards are recognised:
-.Pp
-.Bl -tag -width "-p1003.1g-2000X" -compact
-.It \-p1003.1-88
-.St -p1003.1-88
-.It \-p1003.1-90
-.St -p1003.1-90
-.It \-p1003.1-96
-.St -p1003.1-96
-.It \-p1003.1-2001
-.St -p1003.1-2001
-.It \-p1003.1-2004
-.St -p1003.1-2004
-.It \-p1003.1-2008
-.St -p1003.1-2008
-.It \-p1003.1-2013
-.St -p1003.1-2013
-.It \-p1003.1
-.St -p1003.1
-.It \-p1003.1b
-.St -p1003.1b
-.It \-p1003.1b-93
-.St -p1003.1b-93
-.It \-p1003.1c-95
-.St -p1003.1c-95
-.It \-p1003.1d-99
-.St -p1003.1d-99
-.It \-p1003.1g-2000
-.St -p1003.1g-2000
-.It \-p1003.1i-95
-.St -p1003.1i-95
-.It \-p1003.1j-2000
-.St -p1003.1j-2000
-.It \-p1003.1q-2000
-.St -p1003.1q-2000
-.It \-p1003.2
-.St -p1003.2
-.It \-p1003.2-92
-.St -p1003.2-92
-.It \-p1003.2a-92
-.St -p1003.2a-92
-.It \-p1387.2
-.St -p1387.2
-.It \-p1387.2-95
-.St -p1387.2-95
+The following standards are recognised.
+Where multiple lines are given without a blank line in between,
+they all refer to the same standard, and using the first form
+is recommended.
+.Bl -tag -width 1n
+.It C language standards
+.Pp
+.Bl -tag -width "-p1003.1g-2000" -compact
+.It \-ansiC
+.St -ansiC
+.It \-ansiC-89
+.St -ansiC-89
 .It \-isoC
 .St -isoC
 .It \-isoC-90
 .St -isoC-90
+.br
+The original C standard.
+.Pp
 .It \-isoC-amd1
 .St -isoC-amd1
+.Pp
 .It \-isoC-tcor1
 .St -isoC-tcor1
+.Pp
 .It \-isoC-tcor2
 .St -isoC-tcor2
+.Pp
 .It \-isoC-99
 .St -isoC-99
+.It \-ansiC-99
+.St -ansiC-99
+.br
+The second major version of the C language standard.
+.Pp
 .It \-isoC-2011
 .St -isoC-2011
+.br
+The third major version of the C language standard.
+.El
+.It POSIX.1 before the Single UNIX Specification
+.Pp
+.Bl -tag -width "-p1003.1g-2000" -compact
+.It \-p1003.1-88
+.St -p1003.1-88
+.It \-p1003.1
+.St -p1003.1
+.br
+The original POSIX standard, based on ANSI C.
+.Pp
+.It \-p1003.1-90
+.St -p1003.1-90
 .It \-iso9945-1-90
 .St -iso9945-1-90
+.br
+The first update of POSIX.1.
+.Pp
+.It \-p1003.1b-93
+.St -p1003.1b-93
+.It \-p1003.1b
+.St -p1003.1b
+.br
+Real-time extensions.
+.Pp
+.It \-p1003.1c-95
+.St -p1003.1c-95
+.br
+POSIX thread interfaces.
+.Pp
+.It \-p1003.1i-95
+.St -p1003.1i-95
+.br
+Technical Corrigendum.
+.Pp
+.It \-p1003.1-96
+.St -p1003.1-96
 .It \-iso9945-1-96
 .St -iso9945-1-96
-.It \-iso9945-2-93
-.St -iso9945-2-93
-.It \-ansiC
-.St -ansiC
-.It \-ansiC-89
-.St -ansiC-89
-.It \-ansiC-99
-.St -ansiC-99
-.It \-ieee754
-.St -ieee754
-.It \-iso8802-3
-.St -iso8802-3
-.It \-iso8601
-.St -iso8601
-.It \-ieee1275-94
-.St -ieee1275-94
+.br
+Includes POSIX.1-1990, 1b, 1c, and 1i.
+.El
+.It X/Open Portability Guide version 4 and related standards
+.Pp
+.Bl -tag -width "-p1003.1g-2000" -compact
 .It \-xpg3
 .St -xpg3
+.br
+An XPG4 precursor, published in 1989.
+.Pp
+.It \-p1003.2
+.St -p1003.2
+.It \-p1003.2-92
+.St -p1003.2-92
+.It \-iso9945-2-93
+.St -iso9945-2-93
+.br
+An XCU4 precursor.
+.Pp
+.It \-p1003.2a-92
+.St -p1003.2a-92
+.br
+Updates to POSIX.2.
+.Pp
 .It \-xpg4
 .St -xpg4
+.br
+Based on POSIX.1 and POSIX.2, published in 1992.
+.El
+.It Single UNIX Specification version 1 and related standards
+.Pp
+.Bl -tag -width "-p1003.1g-2000" -compact
 .It \-xpg4.2
 .St -xpg4.2
+.br
+This standard was published in 1994 and is also called SUSv1.
+It was used as the basis for UNIX 95 certification.
+The following three refer to parts of it.
+.Pp
+.It \-xsh4.2
+.St -xsh4.2
+.Pp
+.It \-xcurses4.2
+.St -xcurses4.2
+.Pp
+.It \-p1003.1g-2000
+.St -p1003.1g-2000
+.br
+Networking APIs, including sockets.
+.Pp
 .It \-xpg4.3
 .St -xpg4.3
+.Pp
+.It \-svid4
+.St -svid4 ,
+.br
+Published in 1995.
+.El
+.It Single UNIX Specification version 2 and related standards
+.Pp
+.Bl -tag -width "-p1003.1g-2000" -compact
+.It \-susv2
+.St -susv2
+This Standard was published in 1997
+and is also called X/Open Portability Guide version 5.
+It was used as the basis for UNIX 98 certification.
+The following refer to parts of it.
+.Pp
 .It \-xbd5
 .St -xbd5
-.It \-xcu5
-.St -xcu5
-.It \-xsh4.2
-.St -xsh4.2
+.Pp
 .It \-xsh5
 .St -xsh5
+.Pp
+.It \-xcu5
+.St -xcu5
+.Pp
 .It \-xns5
 .St -xns5
-.It \-xns5.2
-.St -xns5.2
 .It \-xns5.2d2.0
 .St -xns5.2d2.0
-.It \-xcurses4.2
-.St -xcurses4.2
-.It \-susv2
-.St -susv2
+.It \-xns5.2
+.St -xns5.2
+.Pp
+.It \-p1387.2
+.St -p1387.2
+.It \-p1387.2-95
+.St -p1387.2-95
+.br
+POSIX software administration.
+.El
+.It Single UNIX Specification version 3 and related standards
+.Pp
+.Bl -tag -width "-p1003.1g-2000X" -compact
+.It \-p1003.1d-99
+.St -p1003.1d-99
+.br
+Additional real-time extensions.
+.Pp
+.It \-p1003.1j-2000
+.St -p1003.1j-2000
+.br
+Advanced real-time extensions.
+.Pp
+.It \-p1003.1q-2000
+.St -p1003.1q-2000
+.br
+Amendment 7: Tracing [C Language].
+.Pp
+.It \-p1003.1-2001
+.St -p1003.1-2001
 .It \-susv3
 .St -susv3
-.It \-svid4
-.St -svid4
+.br
+This standard is based on C99, SUSv2, POSIX.1-1996, 1d, and 1j.
+It is also called X/Open Portability Guide version 6.
+It is used as the basis for UNIX 03 certification.
+.Pp
+.It \-p1003.1-2004
+.St -p1003.1-2004
+.br
+The second and last Technical Corrigendum.
+.El
+.It Single UNIX Specification version 4
+.Pp
+.Bl -tag -width "-p1003.1g-2000" -compact
+.It \-p1003.1-2008
+.St -p1003.1-2008
+.br
+This standard is also called SUSv4 and
+X/Open Portability Guide version 7.
+.Pp
+.It \-p1003.1-2013
+.St -p1003.1-2013
+.br
+This is the first Technical Corrigendum.
+.El
+.It Other standards
+.Pp
+.Bl -tag -width "-p1003.1g-2000" -compact
+.It \-ieee754
+.St -ieee754
+.br
+Floating-point arithmetic.
+.Pp
+.It \-iso8601
+.St -iso8601
+.br
+Representation of dates and times, published in 1988.
+.Pp
+.It \-iso8802-3
+.St -iso8802-3
+.br
+Ethernet local area networks.
+.Pp
+.It \-ieee1275-94
+.St -ieee1275-94
+.El
 .El
 .Ss \&Sx
 Reference a section or subsection in the same manual page.