basic expression
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How would I filter filename such as the following in r4.0
read01.mpg
read03.mpg
read10.mpg
read11.mpg
and
cin_deva.avi
cin_devb.avi
cin_devc.avi
cin_deve.avi
cin_devf.avi
read01.mpg
read03.mpg
read10.mpg
read11.mpg
and
cin_deva.avi
cin_devb.avi
cin_devc.avi
cin_deve.avi
cin_devf.avi