Re: [bug #66499] Parameter for option -j seems not to be validated and can cause hangs

[Paul Smith]

On Sun, 2024-12-01 at 17:12 +0100, Henrik Carlqvist wrote:
> On Sun,  1 Dec 2024 09:10:04 -0500 (EST)
> "Paul D. Smith" <INVALID.NOREPLY@gnu.org> wrote:
> > F_GETPIPE_SZ will work on Linux but it's not portable (not part of
> > POSIX
> > fcntl)
> 
> Suggestion: Use F_GETPIPE_SZ as a limit when it does exist, if not,
> use some arbitrary big value which usually will be "big enough with a
> margin". I did use 10000 for a similar arbitrary value in my patch at
> https://savannah.gnu.org/bugs/?51200

I was thinking we'd just remove blocking writes to the pipe when we
initialized it, then check the error code when writing.  If we get
EAGAIN we know we ran out of room and we can fail.

-- 
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