From d90d3eb0d0651706795e1c7965974f819d0f1ed0 Mon Sep 17 00:00:00 2001
From: Mike Black W9MDB <mdblack98@yahoo.com>
Date: Sun, 10 Oct 2021 08:33:31 -0500
Subject: [PATCH] Use EAGAIN error to retry when serial port is unavailable
 https://github.com/Hamlib/Hamlib/issues/818

---
 src/iofunc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/iofunc.c b/src/iofunc.c
index 9e27c4298..4114d57ec 100644
--- a/src/iofunc.c
+++ b/src/iofunc.c
@@ -767,7 +767,7 @@ int HAMLIB_API read_string(hamlib_port_t *p,
         do 
         {
             rd_count = port_read(p, &rxbuffer[total_count], 1);
-            if (errno == EBUSY)
+            if (errno == EAGAIN)
             {
                 hl_usleep(5*1000);
                 rig_debug(RIG_DEBUG_WARN, "%s: port_read is busy?\n", __func__);