diff --git a/test/unit/prv.c b/test/unit/prv.c
index 624627e..e775220 100644
--- a/test/unit/prv.c
+++ b/test/unit/prv.c
@@ -59,7 +59,7 @@ test_emit(const char *path)
 }
 
 static void
-test_duplicate(const char *path)
+test_dup(const char *path)
 {
 	/* Ensure that we detect duplicate values being emitted in the Paraver
 	 * trace */
@@ -95,7 +95,183 @@ test_duplicate(const char *path)
 	 * the header has been fixed */
 	OK(prv_close(&prv));
 
-	err("test duplicate OK\n");
+	err("OK");
+}
+
+static int
+count_prv_lines(FILE *f, int64_t time, int row0, long type, long value)
+{
+	int count = 0;
+	char line[1024];
+
+	rewind(f);
+
+	while (fgets(line, 1024, f) != NULL) {
+		if (line[0] != '2')
+			continue;
+
+		int64_t ftime;
+		long frow1, ftype, fvalue;
+		int ret = sscanf(line, "2:0:1:1:%ld:%ld:%ld:%ld",
+				&frow1, &ftime, &ftype, &fvalue);
+
+		if (ret != 4)
+			die("ret=%d", ret);
+
+		if (row0 + 1 != frow1 || time != ftime)
+			continue;
+
+		if (type != ftype || value != fvalue)
+			continue;
+
+		count++;
+	}
+
+	return count;
+}
+
+static void
+test_skipdup(void)
+{
+	/* Test PRV_SKIPDUP flag (skip duplicates) */
+
+	size_t size = 1024;
+	char *buf = calloc(1, size);
+
+	if (buf == NULL)
+		die("calloc failed:");
+
+	FILE *wf = fmemopen(buf, size, "w");
+
+	if (wf == NULL)
+		die("fmemopen failed:");
+
+	FILE *rf = fmemopen(buf, size, "r");
+
+	if (rf == NULL)
+		die("fmemopen failed:");
+
+	/* Disable buffering */
+	setbuf(wf, NULL);
+	setbuf(rf, NULL);
+
+	int64_t time = 0;
+	long type = 100;
+	long value = 1000;
+
+	struct bay bay;
+	bay_init(&bay);
+
+	struct prv prv;
+	OK(prv_open_file(&prv, NROWS, wf));
+
+	struct chan chan;
+	chan_init(&chan, CHAN_SINGLE, "testchan");
+
+	/* Allow setting the same value in the channel */
+	chan_prop_set(&chan, CHAN_ALLOW_DUP, 1);
+
+	OK(bay_register(&bay, &chan));
+	OK(prv_register(&prv, 0, type, &bay, &chan, PRV_SKIPDUP));
+	time += 10000;
+
+	/* Set the initial value */
+	OK(chan_set(&chan, value_int64(value)));
+	OK(prv_advance(&prv, time));
+
+	/* Propagate will emit the value into the PRV */
+	OK(bay_propagate(&bay));
+
+	/* Check for the line */
+	if (count_prv_lines(rf, time, 0, type, value) != 1)
+		die("expected line not found or multiple matches");
+
+	/* Set the same value again, which shouldn't fail */
+	OK(chan_set(&chan, value_int64(value)));
+
+	/* Propagate again, emitting the value */
+	OK(bay_propagate(&bay));
+
+	/* Ensure that we didn't write it again */
+	if (count_prv_lines(rf, time, 0, type, value) != 1)
+		die("expected line not found or multiple matches");
+
+	fclose(wf);
+	fclose(rf);
+
+	err("OK");
+}
+
+static void
+test_emitdup(void)
+{
+	/* Test PRV_EMITDUP flag (emit duplicates) */
+
+	size_t size = 1024;
+	char *buf = calloc(1, size);
+
+	if (buf == NULL)
+		die("calloc failed:");
+
+	FILE *wf = fmemopen(buf, size, "w");
+
+	if (wf == NULL)
+		die("fmemopen failed:");
+
+	FILE *rf = fmemopen(buf, size, "r");
+
+	if (rf == NULL)
+		die("fmemopen failed:");
+
+	/* Disable buffering */
+	setbuf(wf, NULL);
+	setbuf(rf, NULL);
+
+	int64_t time = 0;
+	long type = 100;
+	long value = 1000;
+
+	struct bay bay;
+	bay_init(&bay);
+
+	struct prv prv;
+	OK(prv_open_file(&prv, NROWS, wf));
+
+	struct chan chan;
+	chan_init(&chan, CHAN_SINGLE, "testchan");
+
+	/* Allow setting the same value in the channel */
+	chan_prop_set(&chan, CHAN_ALLOW_DUP, 1);
+
+	OK(bay_register(&bay, &chan));
+	OK(prv_register(&prv, 0, type, &bay, &chan, PRV_EMITDUP));
+	time += 10000;
+
+	/* Set the initial value */
+	OK(chan_set(&chan, value_int64(value)));
+	OK(prv_advance(&prv, time));
+
+	/* Propagate will emit the value into the PRV */
+	OK(bay_propagate(&bay));
+
+	/* Check for the line */
+	if (count_prv_lines(rf, time, 0, type, value) != 1)
+		die("expected line not found or multiple matches");
+
+	/* Set the same value again, which shouldn't fail */
+	OK(chan_set(&chan, value_int64(value)));
+
+	/* Propagate again, emitting the value */
+	OK(bay_propagate(&bay));
+
+	/* Ensure that we write it again */
+	if (count_prv_lines(rf, time, 0, type, value) != 2)
+		die("expected line not found or multiple matches");
+
+	fclose(wf);
+	fclose(rf);
+
+	err("OK");
 }
 
 /* Detect same types being registered to the same row */
@@ -133,7 +309,9 @@ int main(void)
 		die("mkstemp failed:");
 
 	test_emit(fname);
-	test_duplicate(fname);
+	test_dup(fname);
+	test_skipdup();
+	test_emitdup();
 	test_same_type(fname);
 
 	close(fd);