Hello

You said: The example above is ok, but if the file is very large, you might want to use join the data.

Joining the data will not eleminate the problem, it will only delay it (and not by much for that matter). If the file is very large, use: 

use File::Temp qw/tempfile/;
open $FIN, "<$file1" or die ....
my ($fh, $fname) = tempfile();
print $fh "FIRST LINE\n";
print $fh $_ while <$FIN>;
close $FIN;
close $fh;
rename $fname, $file1;

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Code to check success of operations is not included for readability

Aziz,,,

Update: Thanks runrig for the comment. The point is the same, don't read all data into memory when moving data from file to file.

In reply to Re: Re: writing to top of a file by abstracts
in thread writing to top of a file by Anonymous Monk

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