zlib configuration : system vs. bundled

[Alan Bateman]

On 17/05/2019 09:18, Baesken, Matthias wrote:
> Hi Alan,   thanks for the  info .
> Are you aware of  a way to  reliably   see  the info   (e.g. in hs_err  file)   what version of  libz  was used  at runtime ?
>
> On linux (with some luck )   we see it in hs_err  , at least a lot of distros  put the version into the libname , and then it is displayed  in the hs_err section
>
> Dynamic libraries:
>
>   ...   /lib64/libz.so.1.2.8
> ...    /lib64/libz.so.1.2.8
> ...   /lib64/libz.so.1.2.8
>
> On macOSX   you see nothing just because the version is not in the libname :
>
>
> Dynamic libraries:
>
>   ...  /usr/lib/libz.1.dylib
>
I don't have any insight into how libz is built for macOS. One comment 
on this is that the frequency of crashes in libz should be significantly 
reduced in recent releases as the central directory is no longer 
mmapped. At least in my experience, almost every crash I've seen 
involving libz or the zip code is because the zip file is replaced while 
it is mapped.

-Alan