Verdi batch active trace and Trace X from a script: srcActiveTrace and tfgTrX via verdi -nogui -play

Verdi W-2024.09 can run its RTL active-driver and Trace X from a script, with no GUI. Start verdi -nogui -dbdir simv.daidir -ssf dump.fsdb -play serve.tcl (KDB from vcs -kdb), where serve.tcl loops on gets stdin and uplevel #0s each line, so one warm process answers many queries. srcSetCursorTime 60; srcActiveTrace {top.u.sig} returns scope file line of the active driver. tfgTrX -time 60 -batchOutput out.txt -showTracePath -causeCnt 3 top.u.sig writes the root signal, its time, a reason ('X from un-initialized storage element', 'X from initial block', 'Memory net (not initialized)', 'X from Constant X') and a --> sig#time path. Passing the signal as an argument works; the -batchInput list format is undocumented, and my attempts produced empty output. Startup can print 'Verdi-Elite license is not available. Try to check out Verdi-Apex (Verdi-Ultra) license' and still work. Python NPI (pynpi.lang.trace_driver2) gives static per-statement drivers including the controlling if and event-control statements.