Hi John, Thanx for the solution ... Please tell me how to use IO::File module instead of open function in this scenario.

Actually, it's the other way round: you are using IO::File (BTW: to render this link in the source of your node you can use [mod://IO::File]) and he suggested you to use a plain regular open. If you actually read (did you?) his post, you'll notice he gives you and explicit example about how to do so, namely:

my $inFile = q{spw623147.txt};
open my $inFH, q{<}, $inFile
   or die qq{open: $inFile: $!\n};
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So, what's wrong with that?!?

BTW: if you are confused by the alternate delimiters, the use of which in this context may be exaggerate and controversial to some, that can be:

my $inFile = 'spw623147.txt';
open my $inFH, '<', $inFile or die "open: $inFile: $!\n";
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