If write buffering is enabled, then it is necessary to release the write buffer resources (callback structure) when the socket is closed

1 files changed, 11 insertions, 3 deletions

diff --git a/apps/netutils/telnetd/telnetd_driver.c b/apps/netutils/telnetd/telnetd_driver.c
index 13d1e00e4..7f87b8c70 100644
--- a/apps/netutils/telnetd/telnetd_driver.c
+++ b/apps/netutils/telnetd/telnetd_driver.c
@@ -215,7 +215,7 @@ static void telnetd_getchar(FAR struct telnetd_dev_s *priv, uint8_t ch,
  * Name: telnetd_receive
  *
  * Description:
- *   Process a received telenet buffer
+ *   Process a received Telnet buffer
  *
  ****************************************************************************/
 
@@ -500,12 +500,20 @@ static int telnetd_close(FAR struct file *filep)
         }
       else
         {
-          /* Unregister the character driver */
+          /* Un-register the character driver */
 
           ret = unregister_driver(devpath);
           if (ret < 0)
             {
-              nlldbg("Failed to unregister the driver %s: %d\n", devpath, ret);
+              /* NOTE: a return value of -EBUSY is not an error, it simply
+               * means that the Telnet driver is busy now and cannot be
+               * registered now because there are other sessions using the
+               * connection.  The driver will be properly unregistered when
+               * the final session terminates.
+               */
+
+              nlldbg("Failed to unregister the driver %s: %d\n",
+                     devpath, ret);
             }
 
           free(devpath);