next tool - need an integer available to my custom M code

My linuxcnc system works well and I've been a user since 2004. I do have a problem and have , thus far, been unable to solve.

I have written a bash script and called it M102. It fires up great but the argument I pass is not the next tool , from Tn, awaiting the m6.

I want to have the tool next value to index a list of photos which I will display on the monitor. All that is easy stuff but I cannot seem to get the iocontrol.0.tool-number into my axis environment. Global variable needed ?

Can you more experienced fellows help me ?

Bill Phillips
Thank you

selectedtool has the tool number.

#<_selected_tool> is the global parameter for the selected tool (tool called before M6 is executed.)
#<_current_tool> is the global parameter for the current tool in the spindle (after M6)

The hal pins iocontrol.0.tool-prep-number and iocontrol.0.tool-number should should give the same values. (Although I think iocontrol.0.tool-prep-number is changed to 0 after an M6 until a Tn code is used.)

Thank you sir, but same result..My MDI command exactly is M102 P#<selectedtool> and every other conceivable way I can embrace the variables name: including M102 P#<_selectedname>. I've been failing at this ,otherwise simple op for 3 days, almost forgetting the goal.

ideas in the syntax required ?
Thanks

It works as expected, thank you. Of all that I have read not once was that global name discovered. Tell me young man, where should I have looked.

Thanks again.
Bill Phillips

docslip wrote: It works as expected, thank you. Of all that I have read not once was that global name discovered. Tell me young man, where should I have looked.

Thanks again.
Bill Phillips

Right here.
linuxcnc.org/docs/html/gcode/overview.ht...ub:system-parameters