Re: [PATCH 02/20] scripts/make-erofs.sh: Do not read one byte at a time

[Demi Marie Obenour <demiobenour@gmail.com>]

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On 9/8/25 04:23, Alyssa Ross wrote:
> Demi Marie Obenour <demiobenour@gmail.com> writes:
> 
>> POSIX requires that the shell read builtin not consume any bytes beyond
>> the end-of-line character.  For non-seekable files like pipes, this
>> requirement can only be met by reading one byte at a time, which is very
>> slow.  Avoid this by reading the entire input into a temporary file and
>> having sh read from the temporary file.  Since regular files are
>> seekable, sh can read many bytes and then seek back to the correct file
>> position.
> 
> Slow enough to make a noticeable difference in the context of the whole
> script?

Don't know 🙂.  It's just a known antipattern and
I saw bash using a decent amount of CPU time.
-- 
Sincerely,
Demi Marie Obenour (she/her/hers)

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