in reply to Speed reading (files)

IIRC, 
open(FILE,"<$file") || die $!;
my $data = do { local $/; <FILE> };
close(FILE);

[download]
is slower than 
open(FILE,"<$file") || die $!;
my $data;
{ local $/; $data = <FILE> }
close(FILE);

[download]
which is the true traditional slurp.

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Re^2: Speed reading (files)
by kwaping (Priest) on Aug 04, 2005 at 17:48 UTC
    Read is still faster, but the difference is very minute. Using read is still no worse than the true traditional slurp, which I find interesting. 
    using read function
0.614683866500854
0.604650020599365
0.616497039794922
0.640319108963013
0.603079795837402
0.605829000473022

ikegami's code
0.672801971435547
0.667882919311523
0.666944980621338
0.670393943786621
0.712579011917114
0.767023086547852

    [download]
[reply]
[d/l]

      The advantage of "slurping" is that it works with ttys. I don't think -s does.

      Also, is read guaranteed to return the number of bytes requested (if the file is big enough)? sysread isn't.

      As an aside, wouldn't read FILE, my $data, $MAX_FILE_SIZE; be faster than using -s, especially on smaller files? I guess you have to find an acceptable $MAX_FILE_SIZE (in Config.pm, maybe???)

      By the way, I'm not suprised that read is as fast or faster than "slurping". Why wouldn't it be?

[reply]
[d/l]
[select]
        Also, is read guaranteed to return the number of bytes requested (if the file is big enough)? sysread isn't.

        Could you clarify this for me?

        From sysread:

        sysread ... Returns the number of bytes actually read, 0 at end of file, or undef if there was an error ...

        Under what circumstances would sysread fail to return the number of bytes actually requested?

        Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
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[reply]

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