Identify the "yyyymmdd" value from the file name using the below perl regex.

$filename = "ccsCDRFileGenerator-0-24161-1176950330-17914920070419_2.C
+DR";

($yyyymmdd) = $filename =~ m/\d+(\d{8})\_\d+\.CDR$/;

print "DATE is : $yyyymmdd \n"
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Using the DateTime::Precise module, identify yesterday's "yyyymmdd" value. Then you can pickup the files as you want..