Re: file reading issues

There are a couple ways I can think of to do that, offhand. If it's a small file and you can read it all into memory, you can do something like this:

my $file = '/path/to/file.txt';
open(IN,"<$file") || die $!;
read IN, my $html, -s $file;
close(IN);
$html =~ s/<!-- Begin -->(.*?)<!-- End -->/$1/s;
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Or, if the file is large and you'd like to read it line by line, you might want to try setting a flag when Begin is encountered, then turning it off again when End is hit.

my $flag = 0;
while (<FILE>) {
    $flag = 1 if (/<!-- Begin -->/);
    $flag = 0 if (/<!-- End -->/);

    process_line($_) if ($flag);
}
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Comment on Re: file reading issues Select or Download Code

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Re^2: file reading issues by JediWizard (Deacon) on Aug 03, 2005 at 19:19 UTC
I notice you have a different method for reading an entire file into memory then I am used to seeing. I was wondering if there is any reason you are aware of that makes your way better or worse than the way I use (or if they are just different (TIMTOWTDI)). If there is, I'd love to hear about it. `read IN, my $html, -s $file; # your code my $file = do{ local $/; <IN> }; # The way I usually use.` [download] Other monks... can anybody tell me if there is an advantage in one way or the other? Update The secode line of cone above is the way I am used to seeing... I forgot to complete the comment. My question regards the difference between using `$/` as opposed to using `read` to slurp in an entire file. They say that time changes things, but you actually have to change them yourself. —Andy Warhol	[reply] [d/l] [select]
Re^3: file reading issues by kwaping (Priest) on Aug 03, 2005 at 19:36 UTC
What is the way you're used to seeing? Maybe I am the one in need of enlightenment and your way is superior. To answer your question, there is no reason why I do it that way except that's the way I learned how to do it. Maybe there was a good reason to do it like that back then which has now been made moot by advances in Perl - I don't know.	[reply]
Re^4: file reading issues by JediWizard (Deacon) on Aug 04, 2005 at 02:57 UTC
Sorry... apparently I forgot to type part of my question... Allow me to update. They say that time changes things, but you actually have to change them yourself. —Andy Warhol	[reply] [d/l]
Re^5: file reading issues by kwaping (Priest) on Aug 04, 2005 at 15:08 UTC
Re^5: file reading issues by JediWizard (Deacon) on Aug 04, 2005 at 16:49 UTC
Re^3: file reading issues by anonymized user 468275 (Curate) on Aug 04, 2005 at 16:13 UTC
IMO, the difference will be what kind of buffered I/O gets performed. Fuller explanation: Re: Speed reading (files) One world, one people	[reply]