Re: Sequentially numbering output files rather than overwriting an existing file


Do you know where your variables are?
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Re: Sequentially numbering output files rather than overwriting an existing file

by duelafn (Parson)

on Jan 09, 2014 at 00:46 UTC ( [id://1069890]=note: print w/replies, xml )

Need Help??

in reply to Sequentially numbering output files rather than overwriting an existing file

If you don't want to risk races, use sysopen and loop until you can create the file yourself:

#!/usr/bin/perl -w
use strict; use warnings; use 5.010;

use Fcntl qw/ O_CREAT O_EXCL O_WRONLY /;

my $fh = open_next( "Results", ".txt" );
print $fh "Hello!\n";


sub open_next {
    my ($prefix, $suffix) = @_;
    my $number = 0;
    my $FH;
    until (sysopen($FH, ($prefix . ($number || "") .$suffix), O_WRONLY
+|O_EXCL|O_CREAT)) {
        $number++;
    }
    return $FH;
}
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Good Day,
Dean