User`s manual

System Tasks
ModelSim Xilinx User’s Manual Verilog Simulation 5-77
The following system tasks are Verilog-XL system tasks that are not implemented
in ModelSim Verilog, but have equivalent simulator commands.
$input("filename")
This system task read command test from the specified filename. The
equivalent simulator command is do <filename>.
$list[(hierarchical_name)]
This system task lists the source code for the specified scope. The equivalent
functionality is provided by selecting a module in the graphic interface
Structure window. The corresponding source code is displayed in the source
window.
$reset
This system task resets the simulation back to its time 0 state. The equivalent
simulator command is restart.
$restart("filename")
This system task sets the simulation to the state specified by filename, saved
in a previous call to $save. The equivalent simulator command is restore
<filename>.
$save("filename")
This system task saves the current simulation state to the file specified by
filename. The equivalent simulator command is checkpoint <filename>.
$scope(hierarchical_name)
This system task sets the interactive scope to the scope specified by
hierarchical_name. The equivalent simulator command is environment
<pathname>.
$showscopes
This system task displays a list of scopes defined in the current interactive
scope. The equivalent simulator command is show.
$showvars
This system task displays a list of registers and nets defined in the current
interactive scope. The equivalent simulator command is show.