http://qs1969.pair.com?node_id=1138718

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Dear all. I'm a novice perl user. I'm using perl to read a large amount of data but not overly large. So I'm confused why it's hanging. By hanging I mean just sitting there. The state is "S" or sometimes "R" Everywhere I read says to use while ($line = <FILE>) and I did that from the start but still not working. Here is my code:

open (FIND_OUTPUT , "$CT find . -version'brtype($branch)' -print -all +|"); # I only tried to flush the buffer because it's hanging # But still doesn't work select((select(FIND_OUTPUT), $|=1)[0]); while ($line = <FIND_OUTPUT>) { ($filename = $line) =~ s/(.*)@@.*/\1/; ($version = $line)=~ s/(.*)@@(.*)/\2/; #... do a bunch of line processing and put line in hash $ccase_filehash{$filename} .= ";" . $version; } close FIND_OUTPUT; foreach $key (keys %ccase_filehash) { print "$key: $ccase_filehash{$key} \n"; }

When that failed then I tried to write the output to a file instead. That works, the file gets written correctly and it's only 800 KB. But then it hangs either processing the file or printing out the hash

system ("$CT find $vob -version 'brtype($branch)' -print $all > /tmp/f +ind.out"); open (FIND_OUTPUT , "/tmp/find.out"); # This doesn't help but I put it in anyway select((select(FIND_OUTPUT), $|=1)[0]); while ($line = <FIND_OUTPUT>) { ($filename = $line) =~ s/(.*)@@.*/\1/; ($version = $line)=~ s/(.*)@@(.*)/\2/; #... do a bunch of line processing and put line in hash $ccase_filehash{$filename} .= ";" . $version; } foreach $key (keys %ccase_filehash) { print "$key: $ccase_filehash{$key} \n"; }

I should note that when the output of the CT command is smaller then the script doesn't hang. I also tried this without the "select" line to flush the buffer and also didn't work.