.TH r.timestamp
.SH NAME
\fIr.timestamp\fR \- print/add/remove a timestamp for a raster map
.br
.I "(GRASS Raster Program)"
.SH SYNOPSIS
\fBr.timestamp\fR
.br
\fBr.timestamp help\fR
.br
\fBr.timestamp\fR \fBmap=\fIname\fR \fB[date=\fItimestamp[,timestamp]\fR
.SH DESCRIPTION
This command has 2 modes of operation. If no date argument is supplied, then
the current timestamp for the raster map is printed. If a date argument is
specified, then the timestamp for the raster map is set to the specified
date(s).  See EXAMPLES below.

.SH EXAMPLES
.IP "r.timestamp map=soils"
Prints the timestamp for the "soils" raster map. If there is no timestamp for soils,
nothing is printed. If there is a timestamp, one or two lines are printed,
depending on if the timestamp for the map consists of a single date or two dates
(ie start and end dates).
.IP "r.timestamp map=soils date='15 sep 1987'"
Sets the timestamp for "soils" to the single date "15\ sep\ 1987"
.IP "r.timestamp map=soils date='15 sep 1987,20 feb 1988'
Sets the timestamp for "soils" to have the start date "15\ sep\ 1987" and
the end date "20\ feb\ 1988"
.IP "r.timestamp map=soils date=none"
Removes the timestamp for the "soils" raster map
.IP
.LP

.SH "COMMAND LINE OPTIONS"
.LP
Parameters
.IP \fImap\fR
raster map name
.IP \fIdate\fR
date/time stamp or date1,date2 range

.SH "TIMESTAMP FORMAT"
The timestamp values must use the format as described in the GRASS datetime
library.  The source tree for this library should have a description of the
format. For convience, the formats as of Feb, 1996 are reproduced here:

There are two types of datetime values: absolute and relative. Absolute
values specify exact dates and/or times. Relative values specify
a span of time. Some examples will help clarify:
.IP Absolute
The general format for absolute values is

   day month year [bc] hour:minute:seconds timezone

   day is 1-31
   month is jan,feb,...,dec
   year is 4 digit year
   [bc] if present, indicates dates is BC
   hour is 0-23 (24 hour clock)
   mintue is 0-59
   second is 0-59.9999 (fractions of second allowed)
   timezone is +hhmm or -hhmm (eg, -0600)

parts can be missing

   1994 [bc]
   Jan 1994 [bc]
   15 jan 1000 [bc]
   15 jan 1994 [bc] 10 [+0000]
   15 jan 1994 [bc] 10:00 [+0100]
   15 jan 1994 [bc] 10:00:23.34 [-0500]

.IP Relative
There are two types of relative datetime values, year-month and day-second.
The formats are:

   [-] # years # months
   [-] # days # hours # minutes # seconds

The words years, months, days, hours, minutes, seconds are literal
words, and the # are the numeric values. Examples:

   2 years
   5 months
   2 years 5 months
   100 days
   15 hours 25 minutes 35.34 seconds
   100 days 25 minutes
   1000 hours 35.34 seconds

The following are illegal because it mixes year-month and day-second
(because the number of days in a month or in a year vary):

   3 months 15 days
   3 years 10 days


.SH BUGS
Spaces in the timestamp value are required.

.SH AUTHOR
Michael Shapiro, US. Army CERL