Provide an API for controling file locking



Regarding file locking (HDF5_USE_FILE_LOCKING), we have need for opening some files without locking for reading and other files with locking for writing at the same time from the same process.
We are accessing libhdf5 throguh h5py.

It is possible to do so by changing the HDF5_USE_FILE_LOCKING environment variable before each file opening, but that would be cleaner to do that through the API.

Wouldn’t that makes sense to extend the API so toggling file locking can be provided e.g., as and argument when opening the file?