No. I am suggesting to read the filehandle STDIN as you do with your filehandle F - via the diamond operator "<>" or readline. No need to pass STDIN anywhere. 

$| = 1; # turn on autoflush
print "Enter file name: ";
my $answer = <STDIN>;
chomp $answer; # remove newline char from answer
print "file name is '$answer'\n";

[download]
perl -le'print map{pack c,($-++?1:13)+ord}split//,ESEL'

In reply to Re^3: How to read the file from stdin using perl? by shmem
in thread How to read the file from stdin using perl? by gopikavi

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