This has been causing various seemingly spurious CI failures as well as
some failures on people running tests on beta builds.
lix> ++(nix-collect-garbage-dry-run.sh:20) nix-store --gc --print-dead
lix> ++(nix-collect-garbage-dry-run.sh:20) wc -l
lix> finding garbage collector roots...
lix> error: Listing pid 87261 file descriptors: Undefined error: 0
There is no real way to write a proper test for this, other than to
start a process like the following:
int main(void) {
for (int i = 0; i < 1000; ++i) {
close(i);
}
sleep(10000);
}
and then let Lix's gc look at it.
I have a relatively high confidence this *will* fix the problem since I
have manually confirmed the behaviour of the libproc call is
as-unexpected, and it would perfectly explain the observed symptom.
Fixes: lix-project/lix#446
Change-Id: I67669b98377af17895644b3bafdf42fc33abd076