But my script overwrites the earlier data.

Well, then don't do it. Chose a different name for the output file each time you run the system command.

thanks but i I have to do that same thing 1000 times as the array is catching some of my intended data and it is a long file so i cannot generate hundreds of files .Is that its the fault of the software as I cannot automate it .

So you neither want to override the files, nor do you want to preserve them. What do you want?

and it is a long file so i cannot generate hundreds of files

Uhm, why not? A decent computer can handle hundreds of long files, whatever that means.

If disc space is an issue, you could compress the files after they are generated. Or extract the information you want from them, and then delete them.

Perl 6 - second systems done right

viktor:

If you're on a unix box, then you can glue files together like this:

generatefile foo
cat foo >>the_big_file
generatefile foo
cat foo >>the_big_file
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So you can use the same trick in your script. If you're on DOS, there's a similar trick using copy, but you'll have to read the help page on it, as I don't recall it well.

...roboticus

When your only tool is a hammer, all problems look like your thumb.

How I can avoid that .

stop overwriting the file :) use a different filename each time, like

use POSIX;
my $procdate = POSIX::strftime('%Y-%m-%d-%H-%M-%S', localtime);
my $tmsa = "tmsa.out-$procdate";
system .... $tmsa
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How I can avoid that .

Open the file in  >> append mode:

c:\@Work\Perl\junque>perl -wMstrict -e
"my $file = 'junk';
 for my $s (qw(foo bar baz)) {
   open my $fh, '>>', $file    or die qq{opening '$file': $!};
   print $fh qq{this is $s \n} or die qq{writing '$file': $!};
   close $fh                   or die qq{closing '$file': $!};
   }
"

c:\@Work\Perl\junque>cat junk
this is foo
this is bar
this is baz
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As others already pointed out, there's no reason to use hundreds of files, you can easily concatenate them, either on the fly or afterwards... So use a sequence number, time stamp or whatever you like.

I would like to make a few general observations about your code:

• use the 3-argument form of open
• check the result of open
• use lexical file handles

so, in stead if e.g. open (SEQFILE, ">vik.tmp"), use
open my $seqfile, '>', "vik.tmp" or die "cannot open vik.tmp: $!\n";

• also, check the result of close!

close $seqfile or die "cannot close vik.tmp: $!\n";

• no need to join your line before print

print $seqfile @aln is enough