Change "foreach $line2 ( <INFO> ) {..."

to

"while( my $line2 = <INFO> ) {..."

Your current implementation slurps the flat file into memory because foreach is a ranged-based loop that evaluates <INFO> in list context, which gives you slurp behavior. while() is a conditional based loop, and thus evaluates <INFO> in scalar context, which gives you its iterator behavior.

Some hints:

#!/usr/bin/perl
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use strict;
use warnings;
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You mix up several ways to open a file. You should take consistently the three parameter form. Also use scalars as file handles. So your

open (INFO, "<", "$File") or die("Cannot open the flat file");
open(my $LOG,">>LOG_file") or die("Cannot open");
open(XML,">xml_file") or die("Cannot open");
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open(my $INFO, '<', $File) or die "Cannot open the '$File': $!;
open(my $LOG, '>>' 'LOG_file') or die "Cannot open 'LOG_file: $!";
open(my $XML, '>', 'xml_file') or die "Cannot open 'xml_file': $!";
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As stated by davido, you should iterate line by line over the file:

while(defined(my $line2 = <$INFO>)) {
}
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Every $line2 will have a LF at the end. Probably you want to get rid of it. In this case it's not necessary.

chomp $line2;
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It seems you're working on fixed column format files (COBOL output?). The format of the row (line) is defined by the first two bytes (segment). So, instead of creating a big if-elsif-else-tree it would be more maintainable to create a dispatcher based on the segment. The usage of unpack may be your friend to extract the data easily. So I propose the following:

my %config = (
    '00' => {
        'unpack' => "x40A8",
        'fields' => [qw(Var1)],
    },
    'A0' => {
        'unpack' => "x2A9x3A3x3A42A30",
        'fields' => [qw(Var1 Var2 Var3 Var4)],
    },
);

while(defined(my $line = <$INFO>)) {
    my $segment = substr $line, 0, 2;
    if(exists $config{$segment}) {
        my @fields = unpack $config{$segment}->{'unpack'}, $line;
        my %record;
        $record{$config{$segment}->{'fields'}->[$_]} = $fields[$_] for
+each (0..$#fields);
        print Dumper(\%record), "\n";
    }
    else {
        die "ERROR: Unknown segment '$segment'. Config or data error?"
+;
    }
}
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At the end you have to close the filehandles and not the 'filenames':

close $INFO or die "Can't close file '$File': $!";
close $LOG or die "Can't close file 'LOG_file': $!";
close $XML or die "Can't close file 'xml_file': $!";
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These proposals reflect only my personal opinion. Hopefully a little bit helpful.

McA

Hi McA,

Thanks for those suggestions..Even after changing the foreach to while, I'm still facing the same Out of memory issue :-(

Any suggestions?

Thanks & Regards,

sathya V.

If you're still running out of memory, you'll have to find out where you are storing your data and maybe not store all the data in RAM. If you are storing the bulk of your data in a hash, an easy way of trading time for space is to use DB_File or some other key/value store that can be tied to a hash. Update: Also see Tie::DBI, which just had a new release out.

Often it also helps to output progress through your file so that you get an idea where in your program you run out of memory.

In your example you're opening a filehandle named XML, so I assume you want to convert your input stream to xml format. If this is right we would like to see how the xml output is produced. Probably you're using a memory intensive way.

McA

Davido's got your memory fault, but that's pretty inconsistent code formatting, and poor error reporting on the opens. (Remember, $! is your friend, and it never hurts to print the name of the file that failed to open in your error message)

Didnt get what you were referring to regarding the code and open statement. Can you please explain me in detail as I'm new to Perl programming.

Where you have:

open(my $LOG,">>LOG_file") or die("Cannot open");
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Change it to:

open(my $LOG,">>LOG_file") or die("Cannot open: $!");
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This will display more information as to why you couldn't open the file. See open, perlvar and since you're new to perl:

• perlintro
• http://learn.perl.org
• http://perldoc.perl.org
• The tutorials section of this site

use autodie; try a demo

$ perl -e " use autodie; open my($fh), qw[< noexist ]; "
Can't open 'noexist' for reading: 'No such file or directory' at -e li
+ne 1
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the reason it can't open comes from $!