if (pid == 0) {
MPI_File_open(MPI_COMM_SELF, FileName, outMode, MPI_INFO_NULL, &outQuan); //comm, filename, mode, info, filepointer
int length = outputString.length();
if (pid == 0) {
MPI_File_open(MPI_COMM_SELF, FileName, outMode, MPI_INFO_NULL, &outQuan); //comm, filename, mode, info, filepointer
int length = outputString.length();