[gdal-dev] OSRSetPROJSearchPaths in multithreaded application

[Dirk Vanden Boer]

After migrating to gdal 3 I'm having problems performing coordinate
transformations in a multi-threaded application.

My proj.db is in a nonstandard location so I call the
OSRSetPROJSearchPaths once on the main thread before the call to
GDALAllRegister()

I can do coordinate transformations on my main thread, but on worker
threads I get the proj error "Cannot find proj.db".

Calling OSRSetPROJSearchPaths in each worker thread does not seem to
work either.

What is the correct way to get coordinate transformations working on
all my threads?

Kind regards,
Dirk