extend Doxygen description of input method

server/drivers/CFontz633.c

@@ -451,9 +451,10 @@ CFontz633_flush (Driver *drvthis)
 
 
 /**
- * Get next key from the KeyRing.
+ * Get key from the device.
  * \param drvthis  Pointer to driver structure.
- * \return  String representation of the key.
+ * \return         String representation of the key;
+ *                 \c NULL if nothing available / unmapped key.
  */
 MODULE_EXPORT const char *
 CFontz633_get_key (Driver *drvthis)

server/drivers/CFontzPacket.c

@@ -563,9 +563,10 @@ CFontzPacket_flush (Driver *drvthis)
 
 
 /**
- * Get next key from the KeyRing.
+ * Get key from the device.
  * \param drvthis  Pointer to driver structure.
- * \return  String representation of the key.
+ * \return         String representation of the key;
+ *                 \c NULL if nothing available / unmapped key.
  */
 MODULE_EXPORT const char *
 CFontzPacket_get_key (Driver *drvthis)

server/drivers/CwLnx.c

@@ -1384,9 +1384,10 @@ CwLnx_string(Driver *drvthis, int x, int y, const char string[])
 
 
 /**
- * Get next key from the KeyRing.
+ * Get key from the device.
  * \param drvthis  Pointer to driver structure.
- * \return  String representation of the key.
+ * \return         String representation of the key;
+ *                 \c NULL if nothing available / unmapped key.
  */
 MODULE_EXPORT const char *
 CwLnx_get_key(Driver *drvthis)

server/drivers/MtxOrb.c

@@ -1428,6 +1428,7 @@ MtxOrb_cursor (Driver *drvthis, int x, int y, int state)
  * Get key from the LCD/VFD.
  * \param drvthis  Pointer to driver structure.
  * \return         String representation of the key.
+ *                 \c NULL if nothing available / unmapped key.
  *
  * \todo Recover the code for I2C connectivity to MtxOrb
  * and don't query the LCD if it does not support keypad.

server/drivers/hd44780.c

@@ -1219,9 +1219,10 @@ HD44780_icon(Driver *drvthis, int x, int y, int icon)
 
 
 /**
- * Get next key from the key panel connected to the display.
+ * Get key from the key panel connected to the display.
  * \param drvthis  Pointer to driver structure.
- * \return  String representation of the key.
+ * \return         String representation of the key;
+ *                 \c NULL if nothing available / unmapped key.
  */
 MODULE_EXPORT const char *
 HD44780_get_key(Driver *drvthis)

server/drivers/serialPOS.c

@@ -928,9 +928,9 @@ serialPOS_cursor (Driver *drvthis, int x, int y, int state)
 /**
  * Get key from a pass-through port of the POS display.
  * \param drvthis  Pointer to driver structure.
- * \return  String representation of the key.
+ * \return         String representation of the key;
+ *                 \c NULL if nothing available / unmapped key.
  */
-
 MODULE_EXPORT const char *
 serialPOS_get_key (Driver *drvthis)
 {

server/drivers/ula200.c

@@ -971,9 +971,10 @@ ula200_icon (Driver *drvthis, int x, int y, int icon)
 
 
 /**
- * Get next key from the KeyRing.
+ * Get key from the device.
  * \param drvthis  Pointer to driver structure.
- * \return  String representation of the key.
+ * \return         String representation of the key;
+ *                 \c NULL for nothing available / unmapped key.
  */
 MODULE_EXPORT const char *
 ula200_get_key (Driver *drvthis)