Is it possible to read multiple files with a single filehandle in Perl?

Question

I have a few log files like these:

/var/log/pureftpd.log
/var/log/pureftpd.log-20100328
/var/log/pureftpd.log-20100322

Is it possible to load all of them into a single filehandle or will I need to load each of them separately?

score 5 · Answer 1 · edited Mar 29 '10 at 13:56

5

One ugly hack would be this:

local @ARGV = qw(
    /var/log/pureftpd.log 
    /var/log/pureftpd.log-20100328 
    /var/log/pureftpd.log-20100322
);

while(<>) {
    # do something with $_;
}

edited Mar 29 '10 at 13:56

Sinan Ünür

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answered Mar 29 '10 at 09:47

Leon Timmermans

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1

Use the special `ARGV` filehandle to implicitly open on each file in @ARGV. – Pedro Silva Mar 29 '10 at 17:28
This is what I do. I wouldn't call it "ugly", but it's not beautiful either. – brian d foy Mar 29 '10 at 20:12
Well, the reason it's "ugly" is because it's fragile: any other part of your code (or someone else's) can break this code by munging `@ARGV`. For for a quick one-off script, it's fine. – Ryan C. Thompson Apr 20 '10 at 16:27

score 1 · Accepted Answer · answered Mar 29 '10 at 09:40

1

You could use pipes to virtually concat these files to a single one.

answered Mar 29 '10 at 09:40

codymanix

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Thanks, that was the keyword I was looking for. – rarbox Mar 29 '10 at 09:47

score 1 · Answer 3 · answered Mar 29 '10 at 20:14

1

It's not terribly hard to do the same thing with a different filehandle for each file:

foreach my $file ( @ARGV )
    {
    open my($fh), '<', $file or do { warn '...'; next };
    while( <$fh> )
         {
         ...
         }
    }

answered Mar 29 '10 at 20:14

brian d foy

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Is it possible to read multiple files with a single filehandle in Perl?

3 Answers3