How to compare dates?

[Daniel Alexander]

I need to compare 2 dates where one is in the format dd-Mmm-yyy
($due_date) to see if $todays_date is within 14 days (2 weeks) of
approaching $due_date. This is going to be used to scan records in a
database to show me which ones are coming due in the next 14 days so I
know they are "hot". Example:

I have a $due_date of 15-Mar-2000 and $todays_date is (hypothetically)
07-Mar-2000 (in whateve format). I would want to know that I am 14 (or
less) from being overdue.

From reading the man pages I believe I should be able to use [clock
format] to convert 15-Mar-2000 into something I can compare to todays
date using a simple =< if statement. However, I am not exactly sure
how to go about it. Can anybody give me an example of how to convert
that date into something I can compare (within days) to whatever the
current date is?

Thanks in advance,

Daniel Alexander

Sent via Deja.com http://www.deja.com/
Before you buy.

[Nuno Rodrigues]

This is the comversion you should do to put a date in yyyymmdd format.
clock format [clock seconds] -format "%Y%m%d"

Daniel Alexander <alex...@my-deja.com> wrote in message
news:828ptk$ard$1...@nnrp1.deja.com...

[dhag...@my-deja.com]

Read through the docs for the "clock scan" command. Be wary,
however, as it really does not like dash separators, being a
bit US-centric (soon to be fixed in rev 8.3):

# Return -1 if date1 < date2, 0 if date1==date2, 1 if date1 > date2.
proc datecompare {date1 date2} {
regsub -all -- - $date1 " " date1
regsub -all -- - $date2 " " date2
set date1_t [clock scan $date1]
set date2_t [clock scan $date2]
if {$date1_t < $date2_t} {
return -1
} elseif {$date1_t > $date2_t} {
return 1
}
return 0
}

set due_date "15-Mar-2000"
set todays_date [clock format [clock seconds] -format "%m-%b-%Y"]
puts "comparison: [datecompare $todays_date $due_date]"

-=- D. J.

In article <828ptk$ard$1...@nnrp1.deja.com>,

Daniel Alexander <alex...@my-deja.com> wrote:
> I need to compare 2 dates where one is in the format dd-Mmm-yyy
> ($due_date) to see if $todays_date is within 14 days (2 weeks) of
> approaching $due_date. This is going to be used to scan records in a
> database to show me which ones are coming due in the next 14 days so I
> know they are "hot". Example:
>
> I have a $due_date of 15-Mar-2000 and $todays_date is (hypothetically)
> 07-Mar-2000 (in whateve format). I would want to know that I am 14 (or
> less) from being overdue.