Opening a file inside a subroutine for read/write in Perl

Question

I am trying to open a file inside a subroutine to basically substitute some lines in the file. But since, it was not working, I tried a simpler way of printing a line instead of substitute, for debug purposes. Following is the subroutine code.

sub replace {

    while (<INPUT_FILE>){

        my $cell = $_[0];
        our $rpl;

        if ($_=~ /^TASK\|VALUE = (.*)/ ) {

            my $task = $1;
            chomp $task;
            $rpl = $cell . '_' . $task . '_bunch_rpl';
            print "000: $rpl\n";

        }
        elsif ($_=~ /^(.*)\|VALUE = (.*)/ ) {

            my $line = $_;
            chomp $line;
            my $ip_var = $1;
            my $ip_val = $2;
            chomp $ip_var;
            chomp $ip_val;
            my $look= $ip_var."|VALUE";
            open(REPLAY_FILE, "+<$rpl")  || die "\ncannot open $rpl\n";
            while (my $rpl_sub = <REPLAY_FILE>) {
                if ($rpl_sub =~ /^$line/) {
                    print "\n 111: $ip_val";
                }       
            }
            close REPLAY_FILE;
        }
        elsif ($_=~ /^\s*$/) {
            print "\n";
            return ;
        }
    }
}

The code prints the following as of now.

000: lfr_task62_bunch_rpl

 111: 2.0.9.0
 111: INLINE
 111: POWER 
000: aaa_task14_bunch_rpl

Expected output is:

000: lfr_task62_bunch_rpl

 111: 2.0.9.0
 111: INLINE
 111: POWER 
000: aaa_task14_bunch_rpl

 111: 0.45
 111: NO

The input sample is:

    TASK_CELL_NAME|VALUE = lfr
    TASK|VALUE = task62
    TASK_VERSION|VALUE = 2.0.9.0
    CHIP_PKG_TYPE|VALUE = INLINE
    JUNK_LINE = JUNK
    JUNK_LINE = JUNK
    FULL_ESD|VALUE = POWER 

    TASK_CELL_NAME|VALUE = aaa
    TASK|VALUE = task14
    CUSTOM_CELL_DENSITY|VALUE = 0.45
    CUSTOM_CELL_SS|VALUE = NO

Can someone tell me the mistake I am doing here?

UPDATE: Main code below

my @cell_names;

open(INPUT_FILE, "<$ip_file")  || die "\n!!!ERROR OPENING INPUT FILE. EXITING SCRIPT!!!\n";

while (<INPUT_FILE>) {
    if ($_=~ /(.*) =\n/ ) {
        $mw -> messageBox(-message=> "\nFormat not correct on line $. of input file. Exiting script\n");
        exit;
    }
    elsif ($_=~ /(.*) =\s+\n/ ) {
        $mw -> messageBox(-message=> "\nFormat not correct on line $. of input file. Exiting script\n");
        exit;
    }
    elsif ($_=~ /(.*) = \s+(.*)/ ) {
        $mw -> messageBox(-message=> "\nFormat not correct on line $. of input file. Exiting script\n");
        exit;
    }

    elsif ($_=~ /^TASK_CELL_NAME\|VALUE = (.*)/ ) {

        my $cell_name = $1;
        chomp $cell_name;

        unless(grep( /^$cell_name $/, @cell_names )) {
            push @cell_names, "$cell_name ";
            #$count++;
            #print "\nCELL NAME: $cell_name\n";
            replace($cell_name);
        }
    }
}
close INPUT_FILE;

Update: lfr_task62_bunch_rpl before running code:

# Select fund
FUND|VALUE = mmi

# Select bank
BANK|VALUE = citi

# Select cell name
TASK_CELL_NAME|VALUE = lfr

# Select task
TASK|VALUE = task62

# Select task version
TASK_VERSION|VALUE = 1.0.9.0

# Select fund type
FULL_ESD|VALUE = MUTUAL

# Select customer premium
CUSTOM_CELL_SS|VALUE = YES

# Select customer brand density
CUSTOM_CELL_DENSITY|VALUE = 0.76

# Select card chip
CHIP_PKG_TYPE|VALUE|VALUE = OUTLINE

Expected lfr_task62_bunch_rpl after running code:

# Select fund
FUND|VALUE = mmi

# Select bank
BANK|VALUE = citi

# Select cell name
TASK_CELL_NAME|VALUE = lfr

# Select task
TASK|VALUE = task62

# Select task version
TASK_VERSION|VALUE = 2.0.9.0

# Select fund type
FULL_ESD|VALUE = POWER

# Select customer premium
CUSTOM_CELL_SS|VALUE = YES

# Select customer brand density
CUSTOM_CELL_DENSITY|VALUE = 0.76

# Select card chip
CHIP_PKG_TYPE|VALUE|VALUE = INLINE

Answer 1

It's not really clear what this code is supposed to do. But I can immediately see a few problems with the logic. Let's step through a few iterations of the loop, using your sample data file.

The first time, the line of data read in is:

TASK_CELL_NAME|VALUE = lf

So that matches on your second regex match. You set a few variables and then (because $ip_var is equal to "TASK_CELL_NAME") you skip to the else clause and close a filehandle that isn't open.

Next time round, we read:

TASK|VALUE = task62

That matches your first regex match. The variable $rpl_file is set to "XXX_lfr_bunch_rpl" (where 'XXX' is the parameter passed to the subroutine - obviously, I don't know what that is). You print a "000" line with that value and open the file with that name in r/w mode.

Third time round, we get this data:

TASK_VERSION|VALUE = 2.0.9.0

This matches your second regex and because $ip_var isn't equal to "TASK_CELL_NAME" we go into the if clause. This reads from your open filehandle and prints a "111" line. But this generates a warning if you have use warnings switched on as the line includes the value of $rpl_file which is currently defined. It was set the last time around the loop, but because the variable is declared inside the loop, it has now lost its value. We then close the filehandle.

The fourth iteration will be the last one that's really interesting. We get this data:

CHIP_PKG_TYPE|VALUE = INLINE

This also matches the second regex, so we do a lot the same as the third iteration. But the difference here is that when we try to read from the filehandle, we get a warning because that filehandle is closed. Oh, and then we close it again for good measure :-)

As I said at the start, I can't really work out what we're trying to do here. But I can see that the logic is very strange. You really need to go back to the drawing board and think through your logic again.

Update:

With the updated version of your code, I'm still seeing problems.

On the first iteration, the data is:

TASK_CELL_NAME|VALUE = lf

So this matches your second regex. That goes into the piece of code that opens the other file and tries to read from it. But it expects to find the filename in $rpl and that variable hasn't been given a value yet. So the open() fails and the program dies.