2.9.3 INI_VARS issue

Appologies, I just realized that I was testing in current master so I changed to 2.9.3 and there does seem to be something strange going on.

1. If I test with [RS274NGC]INI_VARS = 1 then I can indeed reproduce these issues
2. If I test without [RS274NGC]INI_VARS = 1 (default value is 1) then I can read and write(!) #<_ini[TOOLSETTER]z_tool> (I don't get the error when trying to write)

[edit]
Note this is actually unrelated to the version but to the upper/lower case variable name in the ini file, see below

So it seems to me that it does not like the lowercase entry in the ini file:
If I change this to
I get the expected behavior.

Just went back to current master and I can confirm that the problem is the lowercase variable (or key) name 'z_tool'.

1. A lowercase variable (key) name in the ini file is ignored (eg 'z_tool = 1').
2. If you then want to read the lowercase variable (eg #<_ini[TOOLSETTER]z_tool>) the value is not found because it was never created
3. if you assign a value (eg: #<_ini[TOOLSETTER]z_tool> = 1.2) you actually create a global named parameter

So the key is to ALWAYS use uppercase variables (keys) in the ini file (which should probably be noted somewhere in the documentation)

Lower-case INI file variables are OK in most circumstances.
For example adding this into the Touchy GUI init code (I just happened to have that one in the editor, not a special choice)

And inserting this in the corresponding INI file

Gives this result
So lower case INI variables work in the general case.

But it seems that they do _not_ work in the case of G-code INI-file access.
This is probably because all G-code is lowercased before being sent to the interpreter. And then the bit of the interpreted that reads #<_ini....> variables explicitly uppercases them.
github.com/LinuxCNC/linuxcnc/blob/master..._namedparams.cc#L222

So, the actual situation is that if you want to read an INI variable from G code it must be capitalised, because case info is lost during the process of interpreting the G-code, and the interpeter assumes capitals.

To answer a question from the original posts, you can create a set of global parameters with particular values in the STARTUP_GCODES (would need to be a custom code or subroutine call, though).
But reading from the INI is probably best, accepting the limitations discussed here.