Hi Stephane,
welcome to the list! :-)
The call does not exist, and I wonder which solution is the best. Do I need to wrap all thread creation through genode thread service call ?
indeed, there is no implementation of the pthread API yet. So you will need to implement the needed 'pthread_*' functions. Most applications use only a small subset of the pthread API, which should be straight-forward to implement based on Genode's 'Thread', 'Lock', 'Semaphore' (see 'base/include/base'), and 'Timed_semaphore' (see 'os/include/os'). As long as your application does not rely on advanced pthread features such as real-time scheduling or cancellation handling, the effort will be fairly reasonable.
As a starting point, I recommend looking at our DDE Kit implementation. DDE Kit is a library providing a C-based API including functions for multi-threading and synchonization:
http://genode.org/documentation/api/dde_kit_index
You may either decide to implement 'pthread_create' and the like as wrappers around 'dde_kit_thread_*' functions, or take the DDE kit implementation as blue print for implementing the 'pthread_*' functions directly ontop of the Genode API. You can find the implementation at 'os/src/lib/dde_kit'.
Please note that the current version of libc is not completely thread-safe. In particular, 'errno' is just a plain global variable. If you run into problems with 'errno' reporting strange errors in a multi-threaded application, we should revisit the current 'errno' implementation ('libc/src/lib/libc/errno.cc').
Best regards Norman