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amoss

The thing that I use find for most commonly is to perform a hierarchical grep, i.e

find . -exec grep -Hn regex \{\} \;

How would you do that with the du | grep combo?

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... | xargs grep -Hn regex

This will also be faster, because you fork less.

Using \+ instead of \; will do the same (fork less).

du -a will need to do a stat to get the file size, which is comparatively expensive; I don't think find will (not sure)?

You're right, find won't call stat() unless it needs to. It doesn't need to for recursing through the directory tree because readdir() returns dirent.d_type these days to determine if a name is a directory.

Yes, those stat() calls can be very slow in aggregate on a large tree, especially from HDD (due to seeking) or network filesystem, if the stat information isn't already in cache.

Oh, I forgot about \+. I still pipe to xargs every single time.

Does this deal with arbitrary filenames (having newlines, control chars etc) correctly? Or does Plan9 forbid such filenames?

I've never used plan9. In Linux you do "find -print0 | xargs -0" to deal with that.

Im not sure how one can do \0 separator with du, plan9's du(1) doesn't list such option.

grep -R

but old habits die hard :)

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