in reply to Re: write and read the same file not display the output
in thread write and read the same file not display the output

thanks for the help

Now I am trying in different way, please correct if I am wrong

while ( <$fi> ) {
    #print "$_";
         
             my $a = $1 if /(^$name$)/;
             print $a;
  
}

close $fi;

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But when I run the file output show nothing, and it shows me some message, I am not getting where is the issue please see the below output

perl readwritefile.pl
Use of uninitialized value $a in print at readwritefile.pl line 15, <$
+fi> line 1.
Use of uninitialized value $a in print at readwritefile.pl line 15, <$
+fi> line 2.
Use of uninitialized value $a in print at readwritefile.pl line 15, <$
+fi> line 3.

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Re^3: write and read the same file not display the output
by Rudolf (Pilgrim) on Sep 05, 2012 at 01:53 UTC

    Hello ulaksh, Im guessing youve commented out your print "$_"; on purpose there. Anyway your getting yelled at because when the regex doesnt make a match, $a is not getting defined at all, so it is still undefined. You then try to use it on the next line print $a; You cant print $a because it has no value. It is undefined at the moment. This is also the reason your not getting anything printed to screen. maybe you can try this instead? : 

    print $1 if /^($name)$/;

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[d/l]

      Good eye, Rudolf! Did you mean:

      print $1 if /^($name)$/;

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[d/l]

        Hey thanks for the nice reply, but I was not aware of a difference in the regex with the parentheses (though I updated my post): It would be good if you can point it out for me, always up for learning more Perl ! :-) 

        print $1 if /^$name$/;

#or

print $1 if /^($name)$/;

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[d/l]

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