Loop over the days of a month, in $YYYY$MM$DD format

YYYY=2014; MM=02; for d in $(cal -h $MM $YYYY | grep "^ *[0-9]"); do DD=$(printf "%02d" $d); echo $YYYY$MM$DD; done
Edit YYYY and MM at the beginning of the command with the year and month you want. Note that `DD=$(printf "%02d" $d)` will pad single digit integers with a leading zero. Substitute `echo $YYYY$MM$DD` at the end of the line with the command you want to launch, for instance script.pl --yyyymmdd $YYYY$MM$DD Also available on GitHub as bash util: https://github.com/fibo/yyyymmdd
Sample Output
20140201
20140202
...
20140228

1
By: fibo
2014-02-06 11:31:57

1 Alternatives + Submit Alt

What Others Think

Very nice. I can offer one small improvement and one alternate way of formatting. | tail -6 | head -5 can be replaced with grep (saving one command): | grep "^ *[0-9]" Some (or none) leading space, followed by numbers. "printf" is a shell builtin so it's already quick, but the alternative bash way is: [ ${#DD} = 1 ] && DD=0$DD If DD has length 1, then prefix it with a zero. So my command looks like: YYYY=2014; MM=02; for DD in $(cal $MM $YYYY | grep "^ *[0-9]"); do [ ${#DD} = 1 ] && DD=0$DD; echo $YYYY$MM$DD; done
flatcap · 244 weeks and 1 day ago
@flatcap: thank you for your improvement. I replaced the first submitted version ``` YYYY=2014; MM=02; for d in $(cal $MM $YYYY | tail -6 | head -5); do DD=$(printf "%02d" $d); echo $YYYY$MM$DD; done ``` adding grep "^ *[0-9]" as you suggested. About prefixing with leading zero, I prefer printf, so you can even change format if you want, just editing "%02d".
fibo · 241 weeks ago
Is there any way to modify this command to include the day names? i.e. ``` 2014-02-01 SA 2014-02-02 SU 2014-02-03 MO 2014-02-04 TU 2014-02-05 WE ``` after looking through the commands for cal I haven't had luck myself.
banj · 230 weeks and 3 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

You must be signed in to comment.

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands



Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for: