tcl_flow.d - snoop Tcl execution showing procedure flow using DTrace. tcl_flow.d This traces activity from all Tcl processes on the system with DTrace provider support (tcl8.4.16). This watches Tcl method entries and returns, and indents child method calls. Any Evolving - uses the DTrace Tcl provider, which may change as additional features are introduced. Check Tcl/Readme to see what version these scripts are based on.

Default output, # tcl_flow.d

C CPU-id

TIME(us) Time since boot, us

PID Process ID

CALL Tcl command or procedure name

-> procedure entry

<- procedure return

> command entry

< command return

Watch the first column carefully, it prints the CPU-id. If it changes, then it is very likely that the output has been shuffled.

See the DTraceToolkit for further documentation under the Examples, Notes and Docs directories. The example files may be especially useful as they aim to demonstrate how to interpret the output. tcl_flow.d will run until Ctrl-C is hit. Brendan Gregg [CA, USA] dtrace(1M)