Shell Programming and Scripting

Hello,

Im trying to write a script where it will only execute on a certain day. What would the script look like?

if [ today == monday ]

then do this

is this correct??

And you don't want to use cron?

yes cron will be set to run on say monday but if it isnt monday the script wont run

I don't understand. If your crontab line looks like this:

# Minute Hour DayOfMonth MonthOfYear DayOfWeek(00=Sunday)
00 10 * * 01 yourscript

Then your script will allways only run on monday at 10am.

yeah, but I think the OP also wants to enable 'non-monday' logic into the script as well so that 'nothing happens' if the script is ran on monday from the shell.

if my crontab is set up to run only on the 13th.

0 9 13 * * /script

then my script will need to be setup as - if Monday is the 13 then run the script ifMonday is not the 13th not dont do anything, my question is what will my script look like?

if tuesday is 13 ?

then (run script) ?

else do nothing ?

This should do it:

Code:

if [ $(date +%A) == Monday ]
then
    echo "Can't run on Mondays"
    exit 2
fi

However, in light of this:
I think that the OP has a misunderstanding of how cron works.

My example does not make any distinction on when a Monday falls in a month. My example says run every monday. The asterisk in the crontab's DayOfMonth field says run everyday and then the DayOfWeek is further interpreted to determine which day/days of the week should it run.

Vgresh99 makes a good point so if you want to limit the script from running interactively on Mondays, implement the first example.

I hope this helps