You can get info on the text registers used in an item format (if) spec or xymacros spec (mx, xx or xy_sys) by right clicking on the spec in reading pane of PathFinder, then go to Tools, then select the Macro List or Tag List tool, as appropriate. When the tool completes, you will be prompted to view the resulting DIV.

Hmmm, what I'm trying to track down is where the register gets the text. I'm looking at ISBN numbers, we know they're coming from somewhere but trying to find that database. I get something similar to what you have posted, Shawn, but not sure how to keep looking from there.

Thank you!

Well, I would think you're outputting what's in the text register via <tr> macro? If so, then you have the number of the register, so you can look for a corresponding <cs;#>...<ce> or <px;#>...<pa> that is capturing the ISBN number. Unless they're located externally and they're being fetched via a Perl routine. That's a whole 'nother kettle of fish!

Yes, it's the fish kettle we're after, unfortunately. 

You could search any Perl scripts being run on your JOB/DIV  for "open(" string, which is start of function to "open file" and see if any external file(s) are being accessed. 

I'm not certain I fully understand the situation / environment - but here's an idea that might help:

If you're trying to track down the IF rule responsible for populating the text register, a "brute force" approach would be to have a tag output the contents of the text register as part of the IF prestring (or post string - depending on how things are set up).

Creating a macro named <FindTheTXT> that has the expansion of (where XX is the text register number):

<px><tt;XX;d><mc;%treginfo=1;tr(XX;d);nul><pa> 

Putting FindTheTXT in your prestring (or poststring) would at least tell you which tag contents/code (assuming main text) is responsible for populating the txt register. Once you know that, it would be a matter of tracing through the macros or Perl to see what's going on.

I'm not certain I fully understand the situation / environment - but here's an idea that might help:

If you're trying to track down the IF rule responsible for populating the text register, a "brute force" approach would be to have a tag output the contents of the text register as part of the IF prestring (or post string - depending on how things are set up).

Creating a macro named <FindTheTXT> that has the expansion of (where XX is the text register number):

<px><tt;XX;d><mc;%treginfo=1;tr(XX;d);nul><pa> 

Putting FindTheTXT in your prestring (or poststring) would at least tell you which tag contents/code (assuming main text) is responsible for populating the txt register. Once you know that, it would be a matter of tracing through the macros or Perl to see what's going on.