VTR_open_file - Open .vtr suffixed VTR files.
call VTR_open_file(PREFIX, [PROC_RANK], [NUM_PROCS], [RESTART], FD)
<IN> PREFIX : Input string defining a name of project. <IN> PROC_RANK : Optional input integer. If present, it defines the rank of the calling process (default 0). <IN> NUM_PROCS : Optional input integer. If present, it defines the total number of processes (default 1). <IN> RESTART : Optional input integer. If present, it defines the starting index of the VTR files (default 0). <OUT> FD : Output derived datatype of type VTR_file_handle.
If used in a multi-process application, the call is local to each process (not collective). In a single threaded application, the calling thread has no need to mention PROC_RANK and NUM_PROC parameters.