From: John Stone (
Date: Tue Mar 13 2018 - 14:29:20 CDT

  While I didn't do it yet, this is on my short list of things
going into VMD 1.9.4, because zlib is a dependency for libpng,
and I would like to enable (and thus have to redistribute) libpng
with VMD, at least on linux perhaps on all platforms, by default.
I'm currently swamped so I wasn't planning to work on this for a
couple of weeks, but if you can wait a bit longer, I hope to have
this resolved in the near future, and I will definitely have
a look at the LAMMPS plugin when I'm adding libz to the build/redistrib

  John Stone

On Tue, Mar 13, 2018 at 12:19:48PM -0700, Christian Leitold wrote:
> Hello,
> I recently wanted to read gzippped LAMMPS trajectories with VMD, and it
> turns out this is possible when the right option is defined. In
> particular,¬ lammpsplugin.c looks for the preprocessor variable _USE_ZLIB.
> This was also mentioned for a similar case in post a few weeks ago:
> [1]
> My question is rather basic: HOW exactly do I activate the preprocessor
> macro in practice? When I just add "#define _USE_ZLIB" it
> in¬ lammpsplugin.c, the compilation fails because apparently it cannot
> find the zlib functions:
> lammpsplugin.c:(.text+0x2e3d): undefined reference to `gzgets'
> My guess is that I will need to add a "-lz" linker option at some point,
> but I failed to find out where exactly.
> Thanks,
> Christian
> References
> Visible links
> 1.

NIH Center for Macromolecular Modeling and Bioinformatics
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