Re: [Libguestfs] [nbdkit PATCH] tests: Better quoting for cleanup_fn

On 07/26/22 10:11, Richard W.M. Jones wrote: > On Tue, Jul 26, 2022 at 07:13:41AM +0200, Laszlo Ersek wrote: >> On 07/25/22 16:02, Eric Blake wrote: >>> + for (( _i = 0; _i < $_cleanup_hook_count; ++_i )); do >>> + local -n _hook=_cleanup_hook$_i >>> + "${_hook[@]}" >> >> BTW, "nameref" variables seem like a relatively new addition to bash; >> for example RHEL7 does not have them. Interestingly, the RHEL7 manual >> also does not document a nameref-like construct that *does* work in >> RHEL7, namely: >> >> $ bar=foo >> $ baz=bar >> $ echo ${!baz} >> foo > > Indeed it doesn't work on RHEL 7, eg: > > $ make && make -C tests check TESTS=test-eflags.sh > > leaves tests/eflags.{err,out} around. > > Do you have a patch for this? This should work: local hook=_cleanup_hook$_i eval "\${${hook}[@]}"

Thanks Laszlo > > [...] >> I wonder if the bash release notes mention "nameref" as a more flexible >> version of "indirect expansion"... Hm, nameref was new in bash-4.3 >> <https://lwn.net/Articles/589566/>;, and RHEL7 has bash-4.2.46-35.el7_9, >> so the lack of "nameref" is understandable (not that it matters for >> upstream nbdkit :)); indirect expansion is not mentioned however as a >> similar feature. > > Actually I'd like to keep things working on RHEL 7 if possible. It's > still a widely used RHEL release. > > Rich. >