Can I stop expr removing the leading zero

[alan147]

I am writing a script to archive some log files. It will run on the first day of the month and archive the files from 2 months ago i.e on November 1st it will archive Septembers files. The file name is of the form YYMMDD01.PAZ. The script takes the current month and then subtracts 2 using expr, unfortunately the value returned is missing the leading zero. Below is an extract of the script

if [ "$SOLMON" -ge 3 -o "$SOLMON" -le 12 ]
then
COMPMON=`expr $SOLMON - 2`

Is there a way to preserve the leading zero.

Thanks

Alan

 

[feherke]

Hi

With [tt]printf[/tt] ?

COMPMON=`printf "%02d" $((SOLMON-2))`

Feherke.

http://rootshell.be/~feherke/

 

[alan147]

Thanks, it works perfectly. I didn't think about printf, easy when you know how.

Alan

 

[SamBones]

In the Korn shell you can aso define the environment variable to be two digits, zero filled. It will always be two digits with a leading zero.

typeset -Z2 COMPMON
(( COMPMON = SOLMON - 2 ))

Hope this helps.