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-rw-r--r--src/H5Flow.c34
1 files changed, 13 insertions, 21 deletions
diff --git a/src/H5Flow.c b/src/H5Flow.c
index bd1661a..53124b1 100644
--- a/src/H5Flow.c
+++ b/src/H5Flow.c
@@ -271,6 +271,9 @@ H5F_low_read(H5F_low_t *lf, const H5F_access_t *access_parms,
*
* rky 980816
* Accommodate fancy MPI derived datatype writes.
+ *
+ * rky 980902
+ * For non-block parallel writes, don't change value of lf->eof.
*-------------------------------------------------------------------------
*/
herr_t
@@ -281,10 +284,6 @@ H5F_low_write(H5F_low_t *lf, const H5F_access_t *access_parms,
herr_t ret_value = FAIL;
haddr_t tmp_addr;
-#ifdef HAVE_PARALLEL
- int use_types=0;
-#endif
-
FUNC_ENTER(H5F_low_write, FAIL);
assert(lf && lf->type);
@@ -295,14 +294,20 @@ H5F_low_write(H5F_low_t *lf, const H5F_access_t *access_parms,
#ifdef HAVE_PARALLEL
if (H5F_LOW_MPIO==access_parms->driver &&
access_parms->u.mpio.use_types) {
- /* In the case of fancy use of MPI datatypes, the addr and size
+ /* rky 090902 KLUGE
+ * In the case of fancy use of MPI datatypes, the addr and size
* parameters have a very peculiar interpretation.
* It is logically possible, but quite complex, to calculate
* the physical offset that the last byte to be written will have
* (assuming the write doesn't fail partway thru, which it may).
- * Instead, we fix up the eof _after_ the write
- * (I really don't know if that's OK or not... rky 980816) */
- use_types = access_parms->u.mpio.use_types; /* check after write */
+ * I don't yet fully understand the relationship between
+ * the lf->eof processor-local variable and the file's true eof.
+ * But presumably lf->eof has the correct value at this point,
+ * and we should _not_ change it,
+ * even if the file's true eof differs from the value of lf->eof.
+ * So for now we DO NOTHING!
+ * (Eventually, perhaps we should at least calculate the address
+ * of the last byte of this write, and compare it to lf->eof.) */
} else {
#endif /* HAVE_PARALLEL */
/* writing a simple block of bytes; can check for writing beyond eof */
@@ -330,19 +335,6 @@ H5F_low_write(H5F_low_t *lf, const H5F_access_t *access_parms,
HRETURN_ERROR(H5E_IO, H5E_UNSUPPORTED, FAIL, "no write method");
}
-#ifdef HAVE_PARALLEL
- /* fix up eof for MPI use_type writes */
- if (H5F_LOW_MPIO==access_parms->driver && use_types) {
- /* set logical eof to current physical eof
- * (ephemeral though it may be...) */
- MPI_Offset mpi_offset_size;
- if (MPI_SUCCESS != MPI_File_get_size(lf->u.mpio.f,&mpi_offset_size)) {
- HRETURN_ERROR(H5E_IO, H5E_MPI, FAIL, "couldn't get file size" );
- }
- lf->eof.offset = mpi_offset_size;
- }
-#endif
-
FUNC_LEAVE(ret_value);
}