Date subtraction in Korn shell scripts

[macrun95]

I need to take a date, ie. 031708, and subtract one day from it. I have looked on the Internet to find a way to do this but all I have found is very complex and pretty old (from the late '90s). Is there any easy way to do this other than converting to Julian, subtracting one day, and then converting back to Gregorian? I'm not a Perl or C programmer and there is probably an easy way to do it in those languages. I'm not opposed to doing it in Perl but just don't know much about it.

Thanks,
Eric

[gpraghuram]

I need to take a date, ie. 031708, and subtract one day from it. I have looked on the Internet to find a way to do this but all I have found is very complex and pretty old (from the late '90s). Is there any easy way to do this other than converting to Julian, subtracting one day, and then converting back to Gregorian? I'm not a Perl or C programmer and there is probably an easy way to do it in those languages. I'm not opposed to doing it in Perl but just don't know much about it.

Thanks,
Eric

Do you want to get the yesterdays date from todays date? or from any date you want to get the previous days date.
If your question is 1 then in Bash yu can do this using the date option like this
$ date --date='1 day ago' # past

If your question is 2 then you can write a small shell script to parse the date string into yy,mm,dd format and the deduct the day to get the previous days date

Raghuram