Rohlih, several APIs in parallel HDF5 must be called collectively. H5Gcreate is one of them. A complete list can be found here:
https://www.hdfgroup.org/HDF5/doc/RM/CollectiveCalls.html G. -----Original Message----- From: Hdf-forum [mailto:[email protected]] On Behalf Of MEYNARD Rolih Sent: Wednesday, June 29, 2016 7:31 AM To: [email protected] Subject: [Hdf-forum] Create & open groups with several process Hi, In my computer code, I want to create several groups. Basically, the process of rank 0 should create my groups. Then all the process should access to these groups in order to write data in the dataset. This is a piece of my code to illustrate my request: #include "hdf5.h" #define H5FILE_NAME "File.h5" #define DATASETNAME "My_Array" int main(int argc, char **argv){ //declare variables hid_t file_id, group_id, plist_id; int world_rank, world_size; MPI_Init(&argc, &argv); MPI_Comm_rank(MPI_COMM_WORLD, & world_rank); MPI_Comm_size(MPI_COMM_WORLD, &world_size); //All process have to access to file plist_id = H5Pcreate(H5P_FILE_ACCESS); H5Pset_fapl_mpio(plist_id, MPI_COMM_WORLD, MPI_INFO_NULL); //Create my file file_id = H5Fcreate(H5FILE_NAME, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT); //Only process of rank 0 can create my groups, here we have one group if(world_rank == 0){ group_id = H5Gcreate(file_id, "/MyGroup", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT); } //I want to synchronize my process MPI_Barrier(MPI_COMM_WORLD); hid_t grp; //All process can access on my groups grp = H5Gopen2(file_id, "/MyGroup", H5P_DEFAULT); //release ressources H5Gclose(grp); H5Gclose(group_id); H5Fclose(file_id); H5Pclose(plist_id); MPI_Finalize(); return 0; } My code compiles, but it doesn't run. In particular, I can't open my group. I have a problem about groups here. What is my mistake in this program? Thanks to you Rolih _______________________________________________ Hdf-forum is for HDF software users discussion. [email protected] http://lists.hdfgroup.org/mailman/listinfo/hdf-forum_lists.hdfgroup.org Twitter: https://twitter.com/hdf5 _______________________________________________ Hdf-forum is for HDF software users discussion. [email protected] http://lists.hdfgroup.org/mailman/listinfo/hdf-forum_lists.hdfgroup.org Twitter: https://twitter.com/hdf5
