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A comment on Unix "find" expressions compiled to bytecode. Parent comment

Re:Unix "find" expressions compiled to bytecode by nasretdinov on Friday December 26, 2025 @12:13PM (#46393995)
For many cases you don't even need to make stat() call to determine whether or not the file is a directory (d_type specifically can tell it: https://man7.org/linux/man-pages/man3/readdir.3.html). That's what allows find(1) to be so quick
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Re:Unix "find" expressions compiled to bytecode by loeg on Friday December 26, 2025 @03:23PM (#46395811)
You could imagine determining from the parsed expression whether or not stat'ing was required.

NFS has readdirplus, but I don't think it ever made its way into Linux/POSIX. (Some filesystems could efficiently return dirents + stat information.)

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Re:Unix "find" expressions compiled to bytecode by nasretdinov on Friday December 26, 2025 @03:59PM (#46396195)
> readdirplus

Well, it definitely does _something_, because on NFS the subsequent stat() calls after reading the directory names do indeed complete instantly :), at least in my testing.

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Re:Unix "find" expressions compiled to bytecode by loeg on Friday December 26, 2025 @04:10PM (#46396301)
I mean, readdirplus as a local filesystem API. Ultimately unix programs are just invoking getdents() (or equivalent) + stat() (or statx, whatever). Linux nfsclient probably caches the result of readdirplus for subsequent stat.
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