From 84108f9613c5836be6cc668763d0f40edbe6b59e Mon Sep 17 00:00:00 2001
From: Wouter van Gulik <pa3wle@gmail.com>
Date: Sat, 21 Aug 2021 21:59:02 +0200
Subject: [PATCH] src/rig.c: Add comments to clarify both mode and width must
 be supplied

---
 src/rig.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/rig.c b/src/rig.c
index 28043dd93..979b5dff4 100644
--- a/src/rig.c
+++ b/src/rig.c
@@ -2297,6 +2297,9 @@ int HAMLIB_API rig_set_mode(RIG *rig, vfo_t vfo, rmode_t mode, pbwidth_t width)
  *  The value stored at \a mode location equals RIG_MODE_NONE when the current
  *  mode of the VFO is not defined (e.g. blank memory).
  *
+ *  Note that if either \a mode or \a width is NULL, -RIG_EINVAL is returned.
+ *  Both must be given even if only one is actually wanted.
+ *
  * \RETURNFUNC(RIG_OK) if the operation has been successful, otherwise
  * a negative value if an error occurred (in which case, cause is
  * set appropriately).