$ ls
XYZZY
$ halcmd show sig
Signals:
Type          Value  Name     (linked to)
float             0  Xa
float             0  Xb
float             0  Ya
float             0  Yb

$ halcmd show sig X*                            # Command actually invoked: halcmd show sig XYZZY
Signals:
Type          Value  Name     (linked to)

$ halcmd show sig Y*
Signals:
Type          Value  Name     (linked to)
float             0  Ya
float             0  Yb