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Re: hanging script on read

by stevieb (Canon)
on Aug 16, 2015 at 02:02 UTC ( #1138723=note: print w/replies, xml ) Need Help??

in reply to hanging script on read

Obligatory... please always put use strict;, use warnings; at the top of your scripts, and here's the idiomatic and recommended three-arg open with lexical file-handles:

# read open my $fh, '<', 'file.ext' or die $!; # write open my $wfh, '>', 'file.ext' or die $!;

Peppering the code with print statements to try to find out where the code is 'hanging' might help as well.

To get really nitty gritty once the above have been done, throw in a $DB::single = 1; just above where you think the code is hanging, then, on the command line:

# errata removed $ perl -d # 'continue' and stop at your breakpoint with 'c' main::( $DB::single = 1; DB<1> c # step into your variable with 's' main::( my $x = 'y'; DB<1> s # display to STDOUT the value of the variable with "x $var" main::( print $x; DB<1> x $x 0 'y'

If it hangs above a print or in debugging your breakpoint, you'll know exactly where to focus your attention.

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Re^2: hanging script on read
by Anonymous Monk on Aug 16, 2015 at 17:59 UTC

    Thank you stevie b. I will try to put the use strict; use warnings; at top. Also I know where it hangs. I have used print. In the first code snippet it hangs in the while loop processing the output of the ct find command In the second code snippet it hangs while printing out the hash, e.g. processing the hash in the foreach loop That's why I tried to flush the buffer. So it's unclear to me because it's not like its a super huge amount of data. thank you for your help.

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