>> Can you confirm - are you -really- using 1.1.2??? >> >> You might consider updating to something more recent, like 1.3.0 or >>at least 1.2.8. It would be interesting to know if you see the same >> problem.
> Also, if you could include a short program that reproduces the > problem, that would be most helpful. Hi, thanks for your replies. It's true, I was using 1.1.2. I just switched to 1.3 and I see the same behavior. Here's a sample program. int main( int argc, char *argv[]){ char a2_buff[3] = "aa"; char b1_buff[2] = "b"; MPI_File fh; MPI_Status status; MPI_Init( &argc, &argv ); //write long file aa MPI_File_open( MPI_COMM_WORLD, "foo.txt", MPI_MODE_CREATE | MPI_MODE_WRONLY, MPI_INFO_NULL, &fh ); MPI_File_write_ordered( fh, a2_buff, 2, MPI_BYTE, &status ); MPI_File_close( &fh ); //foo.txt now says "aa" //write short file b MPI_File_open( MPI_COMM_WORLD, "foo.txt", MPI_MODE_CREATE | MPI_MODE_WRONLY, MPI_INFO_NULL, &fh ); MPI_File_write_ordered( fh, b1_buff, 1, MPI_BYTE, &status ); MPI_File_close( &fh ); //foo.txt now says "ba" //but I expect it to say "b" MPI_Finalize(); return 0; }//main