You can use the $vw_dumpfile task to specify the waveform dump filename. The filename is optional. If you do not specify a $vw_dumpfile name or use the $vw_dumpfile system task,the default filename is "wavefile.vwf".
$vw_groupfile ("filename")
This is used to restore a previously saved set of signal groups from "filename".
$vw_group ("groupname", signal1, signal2, ...)
This is used to create a new signal group named "groupname". The list of signals (signal1, signal2, ...) will be added to the group. Only signals that have been probed via the $vw_dumpvars() system task may be viewed.
$vw_jumptotime (newTime)
This is used to scroll the waveform window to the specified time (newTime).
$vw_dumpvars (), $vw_dumpvars (level, signal/module name1, ...)
This is used to specify the set of signals to probe for later viewing. When $vw_dumpvars is specified without any arguments, all signals are dumped. When $vw_dumpvars is specified with arguments, the first argument indicates how many levels below each specified module instance to dump. Either modules or signals may be specified. When the level is specified to be 0, all levels below the listed modules will be dumped. Signals must be dumped to be later viewed.