in reply to Binary Comparision

You're missing a call to binmode(), which is essential for reading and writing binary files under Windows. You're also trying to read a binary file into an array of lines. Binary files don't really have lines, so this won't work. Even if they did, you can't be sure your checker can identify a virus by looking at just one line of a file, so you'll have to be able to match across arbitrary sections of the file.

On a higher level, a virus checker can't really work by loading the entire file into memory - some files you'll have to check won't fit in memory!

-sam

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Re^2: Binary Comparision
by ikegami (Patriarch) on Feb 28, 2007 at 00:10 UTC

    You're missing a call to binmode(),

    The OP used :raw in the open, a suitable alternative. 

    #!perl -l

open(my $fh, '<', $0);
print(substr(<$fh>, -2) eq "\r\n" ?'bin':'txt');  # txt

open(my $fh, '<', $0);
binmode($fh);
print(substr(<$fh>, -2) eq "\r\n" ?'bin':'txt');  # bin

open(my $fh, '<', $0);
binmode($fh, ':raw');
print(substr(<$fh>, -2) eq "\r\n" ?'bin':'txt');  # bin

open(my $fh, '<:raw', $0);
print(substr(<$fh>, -2) eq "\r\n" ?'bin':'txt');  # bin

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Re^2: Binary Comparision
by punklrokk (Scribe) on Feb 28, 2007 at 00:02 UTC
    How would I read the file other than into an array? Is there a way to access it a bit at a time? JP
[reply]

      How would I read the file other than into an array?

      You can read the entire file into a scalar using the following snippet: 

      my $raw_data; { local $/; $raw_data = <FH>; }

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      Is there a way to access it a bit at a time?

      Yes, using read.

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      You can set $/ to a reference to a literal number. Then the file will be read in chunks of that size.

      {
    local $/ = \1024;
    while (<$fh>) {
        # do things with 1k chunks in $_
    }
}

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      After Compline,
      Zaxo

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