Changing Date format

sud · February 23, 2009, 3:38pm

How to change a date stored in a variable to YYYYMMDD.

Variable output is in DD-MON-YY,required format is 'YYYYMMDD'

Thanks,
Sud

danmero · February 23, 2009, 4:20pm

$ echo "23-Feb-09" | \
awk -F- 'BEGIN {split("Jan,Feb,Mar,Apr,May,Jun,Jul,Aug,Sep,Oct,Nov,Dec",_,",");for(i=1;i++<13;)m[_]=i}{printf("20%02d%02d%02d\n", $3, m[$2], $1)}'
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