Thanks everyone for helping. This is the code that worked for me:
################
open (LOG,">pending/" . $subject) or die("Error in opening the file :$!:");
########to replace space with underscore between text#####
$subject =~ s/ /_/g;
############################

In reply to Re^4: use variable as name for new file by Zcity
in thread use variable as name for new file by Zcity

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