Re: [bug #62840] make --version in pipe return SIGPIPE

[Henrik Carlqvist]

On Sat, 30 Jul 2022 13:26:46 -0400 (EDT)
Martin Dorey <INVALID.NOREPLY@gnu.org> wrote:
> Follow-up Comment #2, bug #62840 (project make):
> 
> Just for completeness or academic interest, then, this makes it happen
> reliably for me:
> 
> 
> set -o pipefail; { ruby -we '$stdout.write("x" * 4096)'; make --version; } |
> head -n1; echo $?

It was not a reliable way to reproduce the "bug" here:

-8<-----------------------
bash-4.3$ set -o pipefail; { ruby -we '$stdout.write("x" * 4096)'; make
--version; } | head -n1; echo $?
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx  
...
xxxxxxxxxxxxxxxxGNU Make 4.1
0
-8<-----------------------

But I would agree that it is not a bug. A program writing to a pipe is
expected to get a SIGPIPE and possibly return an error code if the pipe closes
before the program is finished.

However, the program is not guaranteed to get a SIGPIPE, there are also
buffers which the program might be able to write to even though those buffers
might not be emptied by the receiving process.

regards Henrik