diff --git a/src/backend/replication/logical/reorderbuffer.c b/src/backend/replication/logical/reorderbuffer.c
index 40a4c4f497c..cd090ecdfbf 100644
--- a/src/backend/replication/logical/reorderbuffer.c
+++ b/src/backend/replication/logical/reorderbuffer.c
@@ -101,7 +101,7 @@ typedef struct ReorderBufferIterTXNEntry
 	XLogRecPtr	lsn;
 	ReorderBufferChange *change;
 	ReorderBufferTXN *txn;
-	int			fd;
+	File		fd;
 	XLogSegNo	segno;
 } ReorderBufferIterTXNEntry;
 
@@ -182,7 +182,8 @@ static void AssertTXNLsnOrder(ReorderBuffer *rb);
  * subtransactions
  * ---------------------------------------
  */
-static ReorderBufferIterTXNState *ReorderBufferIterTXNInit(ReorderBuffer *rb, ReorderBufferTXN *txn);
+static void ReorderBufferIterTXNInit(ReorderBuffer *rb, ReorderBufferTXN *txn,
+									 ReorderBufferIterTXNState *volatile *iter_state);
 static ReorderBufferChange *
 			ReorderBufferIterTXNNext(ReorderBuffer *rb, ReorderBufferIterTXNState *state);
 static void ReorderBufferIterTXNFinish(ReorderBuffer *rb,
@@ -199,7 +200,7 @@ static void ReorderBufferSerializeTXN(ReorderBuffer *rb, ReorderBufferTXN *txn);
 static void ReorderBufferSerializeChange(ReorderBuffer *rb, ReorderBufferTXN *txn,
 							 int fd, ReorderBufferChange *change);
 static Size ReorderBufferRestoreChanges(ReorderBuffer *rb, ReorderBufferTXN *txn,
-							int *fd, XLogSegNo *segno);
+							File *fd, XLogSegNo *segno);
 static void ReorderBufferRestoreChange(ReorderBuffer *rb, ReorderBufferTXN *txn,
 						   char *change);
 static void ReorderBufferRestoreCleanup(ReorderBuffer *rb, ReorderBufferTXN *txn);
@@ -942,15 +943,23 @@ ReorderBufferIterCompare(Datum a, Datum b, void *arg)
 /*
  * Allocate & initialize an iterator which iterates in lsn order over a
  * transaction and all its subtransactions.
+ *
+ * Note: The iterator state is returned through iter_state parameter rather
+ * than the function's return value.  This is because the state gets cleaned up
+ * in a PG_CATCH block in the caller, so we want to make sure the caller gets
+ * back the state even if this function throws an exception.
  */
-static ReorderBufferIterTXNState *
-ReorderBufferIterTXNInit(ReorderBuffer *rb, ReorderBufferTXN *txn)
+static void
+ReorderBufferIterTXNInit(ReorderBuffer *rb, ReorderBufferTXN *txn,
+						 ReorderBufferIterTXNState *volatile *iter_state)
 {
 	Size		nr_txns = 0;
 	ReorderBufferIterTXNState *state;
 	dlist_iter	cur_txn_i;
 	int32		off;
 
+	*iter_state = NULL;
+
 	/*
 	 * Calculate the size of our heap: one element for every transaction that
 	 * contains changes.  (Besides the transactions already in the reorder
@@ -994,6 +1003,9 @@ ReorderBufferIterTXNInit(ReorderBuffer *rb, ReorderBufferTXN *txn)
 									  ReorderBufferIterCompare,
 									  state);
 
+	/* Now that the state fields are initialized, it is safe to return it. */
+	*iter_state = state;
+
 	/*
 	 * Now insert items into the binary heap, in an unordered fashion.  (We
 	 * will run a heap assembly step at the end; this is more efficient.)
@@ -1056,8 +1068,6 @@ ReorderBufferIterTXNInit(ReorderBuffer *rb, ReorderBufferTXN *txn)
 
 	/* assemble a valid binary heap */
 	binaryheap_build(state->heap);
-
-	return state;
 }
 
 /*
@@ -1161,7 +1171,7 @@ ReorderBufferIterTXNFinish(ReorderBuffer *rb,
 	for (off = 0; off < state->nr_txns; off++)
 	{
 		if (state->entries[off].fd != -1)
-			CloseTransientFile(state->entries[off].fd);
+			FileClose(state->entries[off].fd);
 	}
 
 	/* free memory we might have "leaked" in the last *Next call */
@@ -1496,7 +1506,7 @@ ReorderBufferCommit(ReorderBuffer *rb, TransactionId xid,
 
 		rb->begin(rb, txn);
 
-		iterstate = ReorderBufferIterTXNInit(rb, txn);
+		ReorderBufferIterTXNInit(rb, txn, &iterstate);
 		while ((change = ReorderBufferIterTXNNext(rb, iterstate)) != NULL)
 		{
 			Relation	relation = NULL;
@@ -2338,7 +2348,7 @@ ReorderBufferSerializeChange(ReorderBuffer *rb, ReorderBufferTXN *txn,
  */
 static Size
 ReorderBufferRestoreChanges(ReorderBuffer *rb, ReorderBufferTXN *txn,
-							int *fd, XLogSegNo *segno)
+							File *fd, XLogSegNo *segno)
 {
 	Size		restored = 0;
 	XLogSegNo	last_segno;
@@ -2383,7 +2393,7 @@ ReorderBufferRestoreChanges(ReorderBuffer *rb, ReorderBufferTXN *txn,
 			ReorderBufferSerializedPath(path, MyReplicationSlot, txn->xid,
 										*segno);
 
-			*fd = OpenTransientFile(path, O_RDONLY | PG_BINARY, 0);
+			*fd = PathNameOpenFile(path, O_RDONLY | PG_BINARY, 0);
 			if (*fd < 0 && errno == ENOENT)
 			{
 				*fd = -1;
@@ -2404,12 +2414,12 @@ ReorderBufferRestoreChanges(ReorderBuffer *rb, ReorderBufferTXN *txn,
 		 * end of this file.
 		 */
 		ReorderBufferSerializeReserve(rb, sizeof(ReorderBufferDiskChange));
-		readBytes = read(*fd, rb->outbuf, sizeof(ReorderBufferDiskChange));
+		readBytes = FileRead(*fd, rb->outbuf, sizeof(ReorderBufferDiskChange));
 
 		/* eof */
 		if (readBytes == 0)
 		{
-			CloseTransientFile(*fd);
+			FileClose(*fd);
 			*fd = -1;
 			(*segno)++;
 			continue;
@@ -2431,8 +2441,8 @@ ReorderBufferRestoreChanges(ReorderBuffer *rb, ReorderBufferTXN *txn,
 							 sizeof(ReorderBufferDiskChange) + ondisk->size);
 		ondisk = (ReorderBufferDiskChange *) rb->outbuf;
 
-		readBytes = read(*fd, rb->outbuf + sizeof(ReorderBufferDiskChange),
-						 ondisk->size - sizeof(ReorderBufferDiskChange));
+		readBytes = FileRead(*fd, rb->outbuf + sizeof(ReorderBufferDiskChange),
+							 ondisk->size - sizeof(ReorderBufferDiskChange));
 
 		if (readBytes < 0)
 			ereport(ERROR,