@DEVICE[name] : Returns 1 if the specified name is a character device (such as a serial port), or 0 if not. A trailing : is optional except for the pseudo-devices CLIPn: and TMPn: (to differentiate from possible filenames named "clip" or "tmp5").
Examples:
echo %@device[%comspec]
0
echo %@device[lpt1]
1
echo %@device[com1]
1
echo %@device[com5]
0
echo %@device[clip]
0
echo %@device[clip:]
1
