[Gmsh] upgrading GmshClient to onelab

[Nigel Nunn]

Hi Gmsh,

Sometime before the onelab update, I used GmshClient  (from old
GmshSocket.h) to drive our family of mpi gpu accelerated solvers
(discontinuous Galerkin).  I hooked up a pause button to manage the
mpi fleet, and a few parameters for adjusting runtime results passed
back to Gmsh.

After looking at the classes in [gmsh/contrib/onelab] and
[gmsh/projects/onelab, and the way getdp uses onelab, I am not sure
how to begin upgrading from GmshSocket to onelab.  Can someone please
suggest which of the classes derived from onelab client would do?
First stage is to reproduce what we had with GmshClient :  get Gmsh to
query our solver (mpi proc [0]) for parameters, then launch, pause and
stop a simulation using 4 gpus on a single node (dual Xeon).

runGmshClient() from [gmsh/Common/onelabUtils.cpp] sounds promising,
but which client?

thanks for any help!
Nigel