Phantom "No such file" issue

ImJustAFriend has asked for the wisdom of the Perl Monks concerning the following question:

Hello Monks! Been a long time, but I am in need of some expert knowledge. I have literally fought with this issue all day and it's driving me nuts. Every time I run the script I am getting "Could not open Server IN2 (/tmp/CommonLog.10.10.10.10): No such file or directory". Yet, I can run ls, head, more, cat, etc against /tmp/CommonLog.10.10.10.10 all day long with no issues. Why would Perl think the file doesn't exist when it plainly does.

foreach my $server (@servers) {
        open IN2, "<", $provinfile.$server or die "Could not open Serv
+er IN2 ($provinfile.$server): $!\n";
        open OUT2, ">", $provoutfile or die "Could not open OUT2: $!\n
+";

        while (<IN2>)
        {
                if (/\<13\>/../END OF REPORT/) {
                        #next if /PROXY500/ || /END OF REPORT/;
                        print OUT;
                }
        }
}

close(OUT2);
close(IN2);
[download]

If you see anything wrong or have any thoughts on where I can go from here (went about 40 different ways today and all dead ends), I would appreciate any assistance.

Comment on Phantom "No such file" issue Download Code

Replies are listed 'Best First'.

Re: Phantom "No such file" issue
by Athanasius (Archbishop) on Nov 02, 2018 at 02:53 UTC

Hello ImJustAFriend,

Because you haven’t explicitly stringified the expession $provinfile.$server, the dot functions as a concatenation operator. So the result is a string, but there is no dot character inserted between the two strings. This is obscured by the error message, which does contain an inserted dot character.

Update: It’s good practice to ensure that an error message reflects exactly what’s happening. Here, you can accomplish this with an extra assignment:

for my $server (@servers)
{
    my $full_path = $provinfile . '.' . $server;    # or = "$provinfil
+e.$server";

    open IN2, '<', $full_path
        or die "Could not open Server IN2 ($full_path): $!\n";

    ...
}
[download]

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,