[ale] First three Fridays of a month via a Bash script?

James Sumners james.sumners at gmail.com
Wed Jun 6 11:04:14 EDT 2012


Hmm, that conditional seems to work.

On Wed, Jun 6, 2012 at 10:54 AM, leam hall <leamhall at gmail.com> wrote:
> Would `date +%a` == 'Fri' && (`date +%d` <= 21) or something similar work?
>
> I've not tested it, but that's the track I would take.
>
> Leam
>
> On 6/6/12, James Sumners <james.sumners at gmail.com> wrote:
>> I've been thinking on this one since yesterday and haven't come up
>> with anything. I have a Bash script that I want to run on the first
>> three Fridays of every month. I don't think I can setup such a weird
>> schedule in Cron, so I'm thinking of just running it every Friday and
>> the script will exit without doing anything if it isn't an appropriate
>> day.
>>
>> My preference is to stick with standard utilities and Bash without
>> resorting to something like Python. The problem I'm encountering is
>> that GNU date does relative calculations either from the current
>> system time or from a file's modification time. This means I can't use
>> a contrived date such as the first of every month to do something like
>> `date -d 'first Fridate'`, `date -d 'second Friday'`, and `date -d
>> 'third Friday'` because I can't supply two '-d' parameters (one for
>> the start date and a second for the desired calculation).
>>
>> So, does anyone have any suggestions on how I can do this?

-- 
James Sumners
http://james.roomfullofmirrors.com/

"All governments suffer a recurring problem: Power attracts
pathological personalities. It is not that power corrupts but that it
is magnetic to the corruptible. Such people have a tendency to become
drunk on violence, a condition to which they are quickly addicted."

Missionaria Protectiva, Text QIV (decto)
CH:D 59


More information about the Ale mailing list