diff --git a/rpcrig/rpcrigd.c b/rpcrig/rpcrigd.c
index ac8b1bc5d..9876fab05 100644
--- a/rpcrig/rpcrigd.c
+++ b/rpcrig/rpcrigd.c
@@ -91,7 +91,9 @@ int set_conf(RIG *my_rig, char *conf_parms)
 	while (p && *p != '\0') {
 			/* FIXME: left hand value of = cannot be null */
 		q = strchr(p, '=');
-		if (q) *q++ = '\0';
+		if ( !q )
+			return RIG_EINVAL;
+		*q++ = '\0';
 		n = strchr(q, ',');
 		if (n) *n++ = '\0';
 
diff --git a/tests/rigctl_parse.c b/tests/rigctl_parse.c
index 281236f2a..cc6e3f8bc 100644
--- a/tests/rigctl_parse.c
+++ b/tests/rigctl_parse.c
@@ -661,7 +661,9 @@ int set_conf(RIG *my_rig, char *conf_parms)
 	while (p && *p != '\0') {
 			/* FIXME: left hand value of = cannot be null */
 		q = strchr(p, '=');
-		if (q) *q++ = '\0';
+		if ( !q )
+			return RIG_EINVAL;
+		*q++ = '\0';
 		n = strchr(q, ',');
 		if (n) *n++ = '\0';
 
diff --git a/tests/rigmem.c b/tests/rigmem.c
index 22ab43a38..cf3c33bc3 100644
--- a/tests/rigmem.c
+++ b/tests/rigmem.c
@@ -347,7 +347,9 @@ int set_conf(RIG *rig, char *conf_parms)
 	while (p && *p != '\0') {
 			/* FIXME: left hand value of = cannot be null */
 		q = strchr(p, '=');
-		if (q) *q++ = '\0';
+		if ( !q )
+			return RIG_EINVAL;
+		*q++ = '\0';
 		n = strchr(q, ',');
 		if (n) *n++ = '\0';
 
diff --git a/tests/rigsmtr.c b/tests/rigsmtr.c
index 623cffea9..cdb4f1216 100644
--- a/tests/rigsmtr.c
+++ b/tests/rigsmtr.c
@@ -355,7 +355,9 @@ int set_conf_rig(RIG *rig, char *conf_parms)
 	while (p && *p != '\0') {
 			/* FIXME: left hand value of = cannot be null */
 		q = strchr(p, '=');
-		if (q) *q++ = '\0';
+		if ( !q )
+			return RIG_EINVAL;
+		*q++ = '\0';
 		n = strchr(q, ',');
 		if (n) *n++ = '\0';
 
diff --git a/tests/rigswr.c b/tests/rigswr.c
index b8988c2fb..5c4f578d0 100644
--- a/tests/rigswr.c
+++ b/tests/rigswr.c
@@ -303,7 +303,9 @@ int set_conf(RIG *rig, char *conf_parms)
 	while (p && *p != '\0') {
 			/* FIXME: left hand value of = cannot be null */
 		q = strchr(p, '=');
-		if (q) *q++ = '\0';
+		if ( !q )
+			return RIG_EINVAL;
+		*q++ = '\0';
 		n = strchr(q, ',');
 		if (n) *n++ = '\0';
 
diff --git a/tests/rotctl_parse.c b/tests/rotctl_parse.c
index 9600a910a..553ddad11 100644
--- a/tests/rotctl_parse.c
+++ b/tests/rotctl_parse.c
@@ -555,7 +555,9 @@ int set_conf(ROT *my_rot, char *conf_parms)
 	while (p && *p != '\0') {
 			/* FIXME: left hand value of = cannot be null */
 		q = strchr(p, '=');
-		if (q) *q++ = '\0';
+		if ( !q )
+			return RIG_EINVAL;
+		*q++ = '\0';
 		n = strchr(q, ',');
 		if (n) *n++ = '\0';