Re: [Bug] modules zsh/tcp, zsh/zftp unloadable, probably affecting most modern Linuxes

["Marcus Müller" <marcus_zsh@hostalia.de>]

Bit more debugging: Doesn't work with Fedora 30 / glibc 2.29, does work with OpenSUSE leap 
15.2 / glibc 2.26.

For that reason I must assume the regression must have appeared between release 2.26 in 
August 2017 and release 2.29 in Februrary 2019.

On 04.06.23 15:51, Marcus Müller wrote:
> Dear ZSH community,
>
> I just opened a Fedora bug[1], since I suspected this to a configuration-vs-facts 
> mistake in the build, but it turns out that this happens on debian, too, and that I can 
> see in the source code that the offending function is actually used – which should have 
> made linkage fail, but it only does so at dynamic runtime linking.
>
> Don't really know how to go from there – someone would have to rework name resolution to 
> use getaddrinfo/freeaddrinfo (which is POSIX) instead of getipnodebyname/freehostent 
> (which isn't POSIX).
>
> I see that this already happened, in 2007, in commit 
> a5187bb6ac96cc43f68367c5dc9332854c250713, "23670: use getaddrinfo() and getnameinfo() 
> instead of get*by* functions.", but was promptly reverted 30 minutes later without 
> explanation. Maybe it's time to revisit that? Maybe it's also just a sign that the code 
> hasn't been used by anyone in roughly forever, and deserves to be not built on the 
> platforms it doesn't support, or removed altogether.
>
> Bug description:
>
> when running `zmodload zsh/zftp`, it fails due to missing symbol `freehostent`. This is 
> worrisome, because a) that's a broken feature, and b) `freehostent` shouldn't be used on 
> glibc systems (far as I can tell) – `man freehostent` tells us that the function is 
> *not* present in glibc and deprecated.
>
> Steps to Reproduce:
> 1. clean F37 or F38 or debian stable installation
> 2. `sudo dnf --refresh install -y zsh`
> 3. `zsh`
> 4. in zsh: `zmodload zsh/zftp`
>
> Actual Results:
> zsh: failed to load module `zsh/zftp': /usr/lib64/zsh/5.9/zsh/zftp.so: undefined symbol: 
> freehostent
>
> Expected Results:
> loading of module
>
> Best regards,
> Marcus Müller
>
>
> [1] https://bugzilla.redhat.com/show_bug.cgi?id=2212160
>