| -d   |  Enable debugging message display.  | 
 | -h   |  Hang up a possibly open telephone connection on the selected interface.  | 
 | -k   |  Send the specified string using the keypad facility information element.  | 
 | -n   |  Dial the specified number on the selected interface.  | 
 | -u   |  Set the unit number to specify the interface used.  | 
 | -v   |  Enable verbose result messages for dialling (-n and -w)  | 
 | -w   |  After dialling (using the -n option), wait for the first result message.  | 
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