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in reply to Re^2: greater efficiency required (ls, glob, or readdir?)
in thread greater efficiency required (ls, glob, or readdir?)

using ls has some advantages.

That's why some use glob.

Doing it in pure Perl requires several lines

It would take more than 7 lines to do the equivalent of or die $! when using cat. It's so complex you probably don't even bother doing it.

The OP's code is the perfect example. By using cat,

Update: Added OP as an example.

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Re^4: greater efficiency required (ls, glob, or readdir?)
by JavaFan (Canon) on Aug 27, 2008 at 19:23 UTC
    It would take more than 7 lines to do the equivalent of or die $! when using cat. 
        die if $?;

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    only takes one short line.
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      Do you deem "Died at x.pl line y." acceptable for something that could be an I/O or spawning error? (It doesn't if it is and which it is).
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        In this case, cat outputs its own error with what would be $!. 

        cat: file-that-does-not-exist: No such file or directory

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        It might be cleaner to "exit 1 if $?" rather than die to avoid the useless "Died" message (but then you don't get the line number).

        Update: Hmmm, when I hit 'reply', the node I replied to said only, Do you deem "Died at x.pl line y." acceptable?

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        Oh, if you don't like the died message, replace it with 
           exit 1 if $?;

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        A few character strokes more, but still a very short line.

        And no, the program won't be silent. "cat" is perfectly able to tell the user why it can't read the file.

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