Export the topology as a synthetic string.
buflen characters will be written in
buffer, including the terminating \0.
This exported string may be given back to hwloc_topology_set_synthetic().
flags is a OR'ed set of hwloc_topology_export_synthetic_flags_e.
- The number of characters that were written, not including the terminating \0.
-1 if the topology could not be exported, for instance if it is not symmetric.
- A 1024-byte buffer should be large enough for exporting topologies in the vast majority of cases.