Debian package idea: command line timediff

[mrflash818]

2010-10-17 Idea!
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Creating a new simple, but useful way to quickly determine the difference between two dates as a command line program:

timediff [options] date1 [date2]

where

dates are in ISO 8601 ( http://en.wikipedia.org/wiki/ISO_8601 )

options
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specify the units of time between system time and date1, or between date1 and date2:

-ms milliseconds
-s seconds
-m minutes
-h hours
-d days **default**

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So, this might be the idea that gets me started as an active Debian developer.
Goal: to write the program in C as a command-line utility. Will need to learn all the Debian auto tools.

Eventual Goal: for inclusion into Debian unstable, with the desire it become a useful item for others to use, and migrate to Debian Stable.
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2010-11-06

Researching existing libraries and source code to use for the accurate determination of the number of days per month per calendar year.

1st idea: the unix 'cal' program. Searching the Debian Lenny Stable repository finds
a. http://packages.debian.org/lenny/bsdmainutils
b. http://packages.debian.org/lenny/bsdutils
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2010-11-20

Discovered that Debian has "cal" in this package:
http://packages.debian.org/stable/utils/util-linux

Downloaded, uncompressed, and "cal" lives at:
util-linux-ng-2.13.1.1/misc-utils/
cal.1
cal.c
README.cal

Goal: See if it will be a reasonable effort to have the "cal" program's algorithm compute an exact integer for the number of days for any A.D. date of yyyy-mm-dd.

If I can do so, then this will be a successful approach for timediff.
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