Wouldn't (-f $dir/$file) be a faster test for the existence of a (ordinary) file in a directory than either of the other methods?

To explain the comparative behaviour roughly: shelling out has a fixed overhead; the ls command will have been optimised for the platform. opendir/readdir on the other hand has variable overheads, is probably not optimised for a fixed platform, so will begin cheaper but grow with the filecount to eventually overtake the fixed overhead of shelling out.

One world, one people

In reply to Re: opendir slower than ls on large dirs? by anonymized user 468275
in thread opendir slower than ls on large dirs? by Anonymous Monk

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