Clean up date handling,

as a first step to get rid of the frequent petty warnings in this area:
 - always store dates as strings, not as seconds since the Epoch
 - for input, try the three most common formats everywhere
 - for unrecognized format, just pass the date though verbatim
 - when there is no date at all, still use the current date
Originally triggered by a one-line patch from Tim van der Molen,
<tbvdm at xs4all dot nl>, which is included here.
Feedback and OK on manual parts from jmc@.
"please check this in" kristaps@

2 files changed, 58 insertions, 70 deletions

diff --git a/share/man/man7/man.7 b/share/man/man7/man.7
index 5075e5992f2..5f5d878675f 100644
--- a/share/man/man7/man.7
+++ b/share/man/man7/man.7
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: man.7,v 1.16 2011/01/25 00:37:39 schwarze Exp $
+.\"	$OpenBSD: man.7,v 1.17 2011/03/07 01:35:33 schwarze Exp $
 .\"
 .\" Copyright (c) 2009, 2010 Kristaps Dzonsons <kristaps@bsd.lv>
 .\"
@@ -14,7 +14,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: January 25 2011 $
+.Dd $Mdocdate: March 7 2011 $
 .Dt MAN 7
 .Os
 .Sh NAME
@@ -118,15 +118,6 @@ rendered as an empty line.
 .Pp
 In macro lines, whitespace delimits arguments and is discarded.
 If arguments are quoted, whitespace within the quotes is retained.
-.Ss Dates
-The
-.Sx \&TH
-macro is the only
-.Nm
-macro that requires a date.
-The form for this date is the ISO-8601
-standard
-.Cm YYYY-MM-DD .
 .Ss Scaling Widths
 Many macros support scaled widths for their arguments, such as
 stipulating a two-inch paragraph indentation with the following:
@@ -762,26 +753,27 @@ The paragraph left-margin width is reset to the default.
 Sets the title of the manual page with the following syntax:
 .Bd -filled -offset indent
 .Pf \. Sx \&TH
-.Cm title section
-.Op Cm date Op Cm source Op Cm volume
+.Ar title section date
+.Op Ar source Op Ar volume
 .Ed
 .Pp
-At least the upper-case document
-.Cm title
-and the manual
-.Cm section
-arguments must be provided.
-The
-.Cm date
-argument should be formatted as described in
-.Sx Dates ,
-but will be printed verbatim if it is not.
-If the date is not specified, the current date is used.
-The
-.Cm source
+Conventionally, the document
+.Ar title
+is given in all caps.
+The recommended
+.Ar date
+format is
+.Sy YYYY-MM-DD
+as specified in the ISO-8601 standard;
+if the argument does not conform, it is printed verbatim.
+If the
+.Ar date
+is empty or not specified, the current date is used.
+The optional
+.Ar source
 string specifies the organisation providing the utility.
 The
-.Cm volume
+.Ar volume
 string replaces the default rendered volume, which is dictated by the
 manual section.
 .Pp
diff --git a/share/man/man7/mdoc.7 b/share/man/man7/mdoc.7
index 9a99458f65b..ded74931214 100644
--- a/share/man/man7/mdoc.7
+++ b/share/man/man7/mdoc.7
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: mdoc.7,v 1.65 2011/02/07 00:02:50 schwarze Exp $
+.\"	$OpenBSD: mdoc.7,v 1.66 2011/03/07 01:35:33 schwarze Exp $
 .\"
 .\" Copyright (c) 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
 .\" Copyright (c) 2010 Ingo Schwarze <schwarze@openbsd.org>
@@ -15,7 +15,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: February 7 2011 $
+.Dd $Mdocdate: March 7 2011 $
 .Dt MDOC 7
 .Os
 .Sh NAME
@@ -197,34 +197,6 @@ Thus, the following produces
 .Ed
 .Pp
 In free-form mode, quotes are regarded as opaque text.
-.Ss Dates
-There are several macros in
-.Nm
-that require a date argument.
-The canonical form for dates is the American format:
-.Pp
-.D1 Cm Month Day , Year
-.Pp
-The
-.Cm Day
-value is an optionally zero-padded numeral.
-The
-.Cm Month
-value is the full month name.
-The
-.Cm Year
-value is the full four-digit year.
-.Pp
-Reduced form dates are broken-down canonical form dates:
-.Pp
-.D1 Cm Month , Year
-.D1 Cm Year
-.Pp
-Some examples of valid dates follow:
-.Pp
-.D1 "May, 2009" Pq reduced form
-.D1 "2009" Pq reduced form
-.D1 "May 20, 2009" Pq canonical form
 .Ss Scaling Widths
 Many macros support scaled widths for their arguments, such as
 stipulating a two-inch list indentation with the following:
@@ -886,8 +858,10 @@ block.
 Publication date of an
 .Sx \&Rs
 block.
-This should follow the reduced or canonical form syntax described in
-.Sx Dates .
+Recommended formats of arguments are
+.Ar month day , year
+or just
+.Ar year .
 .Ss \&%I
 Publisher or issuer name of an
 .Sx \&Rs
@@ -1469,17 +1443,36 @@ This is the mandatory first macro of any
 manual.
 Its syntax is as follows:
 .Pp
-.D1 Pf \. Sx \&Dd Op Ar date
+.D1 Pf \. Sx \&Dd Ar month day , year
 .Pp
 The
-.Ar date
-may be either
-.Ar $\&Mdocdate$ ,
-which signifies the current manual revision date dictated by
+.Ar month
+is the full English month name, the
+.Ar day
+is an optionally zero-padded numeral, and the
+.Ar year
+is the full four-digit year.
+.Pp
+Other arguments are not portable; the
+.Xr mandoc 1
+utility handles them as follows:
+.Bl -dash -offset 3n -compact
+.It
+To have the date automatically filled in by the
+.Ox
+version of
 .Xr cvs 1 ,
-or instead a valid canonical date as specified by
-.Sx Dates .
-If a date does not conform or is empty, the current date is used.
+the special string
+.Dq $\&Mdocdate$
+can be given as an argument.
+.It
+A few alternative date formats are accepted as well
+and converted to the standard form.
+.It
+If a date string cannot be parsed, it is used verbatim.
+.It
+If no date string is given, the current date is used.
+.El
 .Pp
 Examples:
 .Dl \&.Dd $\&Mdocdate$
@@ -2771,9 +2764,12 @@ does not start a new line.
 \*[hist]
 .It
 .Sx \&Dd
-without an argument prints
-.Dq Epoch .
-In mandoc, it resolves to the current date.
+with non-standard arguments behaves very strangely.
+When there are three arguments, they are printed verbatim.
+Any other number of arguments is replaced by the current date,
+but without any arguments the string
+.Dq Epoch
+is printed.
 .It
 .Sx \&Fl
 does not print a dash for an empty argument.