Perl: Weird Tie::File behaviour in Windows as opposed to Unix - windows

Question

I have this perl script that uses Tie::File.
In Linux(Ubuntu) when I invoke the script via Bash it works as expected but in Windows when I invoke the script via Powershell it behaves weirdly (check P.S. below).
Code:
#!/usr/bin/perl -T
use strict;
use warnings;
use Tie::File;
use CommonStringTasks;
if ( #ARGV != 4 ) {
print "ERROR:Inadequate/Redundant arguments.\n";
print "Usage: perl <pl_executable> <path/to/peer_main.java> <peer_main.java>\n";
print " <score_file_index> <port_step_index>\n";
print $ARGV[0], "\n";
print $ARGV[1], "\n";
print $ARGV[2], "\n";
print $ARGV[3], "\n";
exit 1;
}
my $PEER_DIR = $ARGV[0];
my $PEER_FILE = $ARGV[1];
my $PEER_PACKAGE = "src/planetlab/app";
my $PEER_PATH = "${PEER_DIR}/${PEER_PACKAGE}/${PEER_FILE}";
# Check if args are tainted ...
# Check $PEER_PATH file permissions ...
open(my $file, "+<", "$PEER_PATH")
or
die("File ", $PEER_FILE, " could not be opened for editing:$!");
# Edit the file and change variables for debugging/deployment setup.
# Number demanglers:
# -flock -> arg2 -> 2 stands for FILE_EX
# Options (critical!):
# -Memory: Inhibit caching as this will allow record changes on the fly.
tie my #fileLines,
'Tie::File',
$file,
memory => 0
or
die("File ", $PEER_FILE, " could not be tied with Tie::File:$!");
flock $file, 2;
my $i = 0;
my $scoreLine = "int FILE_INDEX = " . $SCORE . ";";
my $portLine = "int SERVER_PORT = " . $PORT . ";";
my $originalScoreLine = "int FILE_INDEX =";
my $originalPortLine = "int SERVER_PORT =";
(tied #fileLines)->defer;
while (my $line = <$file>) {
if ( ($line =~ m/($scoreLine)/) && ($SCORE+1 > 0) ) {
print "Original line (score): ", "\n", $scoreLine, "\n";
chomp $line;
$line = substr($line, 0, -($scoreDigits+1));
$line = $line . (++$SCORE) . ";";
print "Editing line (score): ", $i, "\n", trimLeadSpaces($fileLines[$i]), "\n";
$fileLines[$i] = $line;
print "Line replaced with:\n", trimLeadSpaces($line), "\n";
next;
}
if ( ($line =~ m/($portLine)/) && ($PORT > 0) ) {
print "Original line (port): ", "\n", $portLine, "\n";
chomp $line;
$line = substr($line, 0, -($portDigits+1));
$line = $line . (++$PORT) . ";";
print "Editing line (port): ", $i, "\n", trimLeadSpaces($fileLines[$i]), "\n";
$fileLines[$i] = $line;
print "Line replaced with:\n", trimLeadSpaces($line), "\n";
last;
}
# Restore original settings.
if ( ($line =~ m/($originalScoreLine)/) && ($SCORE < 0) ) {
print "Restoring line (score) - FROM: ", "\n", $fileLines[$i], "\n";
$fileLines[$i] = " private static final int FILE_INDEX = 0;";
print "Restoring line (score) - TO: ", "\n", $fileLines[$i], "\n";
next;
}
if ( ($line =~ m/($originalPortLine)/) && ($PORT < 0) ) {
print "Restoring line (port) - FROM: ", "\n", $fileLines[$i], "\n";
$PORT = abs($PORT);
$fileLines[$i] = " private static final int SERVER_PORT = " . $PORT . ";";
print "Restoring line (port) - TO: ", "\n", $fileLines[$i], "\n";
last;
}
} continue {
$i++;
}
(tied #fileLines)->flush;
untie #fileLines;
close $file;
The perl version in both OSes is 5+(in Windows Active-State Perl with CPAN modules).
Could it be the way I open the filehandle? Any ideas anyone?
P.S.: The first version had a while (<$file>) and instead of $line I used the $_ variable but when I did that I had a behaviour where specific lines would not be edited but instead the file would get appended with a hundred newlines or so followed by the (correctly) edited line and so on. I also had a warning about $fileLines[$i] being uninitialized!Clearly something's wrong with the Tie::File structure in Windows or something else that I am not aware of. Same erratic behaviour takes place with the changes and in Linux(Ubuntu) behaviour again is as expected.

Answer 1

The OPs question is vague, and lacks input and expected output. Therefore I will simply note some of my concerns:
First, using Tie::File and <$file> and flock on the same handle seems to be both overkill and dangerous. I would recommend simply using Tie::File to iterate and to edit, such as:
#!/usr/bin/env perl
use strict;
use warnings;
use Tie::File;
tie my #lines, 'Tie::File', 'filename';
foreach my $linenum ( 0..$#lines ) {
if ($lines[$linenum] =~ /something/) {
$lines[$linenum] = 'somethingelse';
}
}
Perhaps better than edit inline, as Tie::File allows, copy the file to a backup, iterate over the lines using <$file>, then write to a new file with the old name.
#!/usr/bin/env perl
use strict;
use warnings;
use File::Copy 'move';
my $infile = $ARGV[0];
move( $infile, "$infile.bak");
open my $inhandle, '<', "$infile.bak";
open my $outhandle, '>', $infile;
while( my $line = <$inhandle> ) {
if ($line =~ /something/) {
$line = 'somethingelse';
}
print $outhandle $line;
}
Second, the -MModule flag simply translates to a use Module; at the top of the script. Therefore -MCPAN is use CPAN;, however loading the CPAN module does nothing for the script. CPAN.pm gives a script the ability to install modules.
Third, we will be able to help better if you give and example input, an expected output, and a stripped down script that clearly shows how this operation is to perform while still failing in the same way that the actual script does.

Answer 2

I found out the source of my problems. The reason was the record separator!
Tie::File expected in Windows a /r/n record separator so it read the whole file in just one pass. My files are in UTF-8, with Unix line endings.
That is why when I was traversing the $fileLines and accessed any index beyond 0 I got from perl a warning that the string was not initialized. Fixed the problem and now I am ready to go on! :D
P.S.: Mr Joel Berger I am marking your answer as valid/appropriate because you really tried helping me and I followed your first advice about the file handle :).
Thank you everyone for assisting me xD xD xD