Funny enough, that's *exactly* what I tried to do, but I ran into problems getting the variable to display in customize-variable (a problem with what I put in cus-start.el?) and if I manually used setq it didn't seem to get translated correctly by the way I coded the macro. However, I'll try again next weekend and maybe you'll see a pull request from me sometime. Michael On Mon, Sep 13, 2021 at 12:05 PM Eli Zaretskii wrote: > > From: Michael Gallagher - NOAA Affiliate > > Date: Mon, 13 Sep 2021 11:54:59 -0600 > > Cc: Eli Zaretskii , 50506@debbugs.gnu.org > > > > Eli, as far as your suggestions, these requirements make sense to me. I > took a crack at modifying xdisp.c > > and was able to display ascii characters by appending to lnum_buf before > the numbers are displayed. > > However, when I tried to hook that into the lisp code and add a variable > so that it wouldn't be hardcoded (a > > must, of course) I fell flat on my face. Converting between character > lisp variables to the appropriate C types > > is above my "undergrad CSCI refresher" pay grade. I wish I could be more > helpful but if I were to be the one > > to submit a pull request I would probably need someone to hold my hand. > > It's not too complicated. A character is just an integer in Emacs, > and the way to get a C integer from a Lisp integer is by using the > XFIXNAT macro. > > Look for the code which handles display-fill-column-indicator-mode, in > particular how it takes the indicator character from > Vdisplay_fill_column_indicator_character and adds it to a screen line. > What you need to do is very similar. > -- Michael Gallagher, PhD CIRES Research Scientist Polar Observations and Processes Team (ESRL/NOAA/PSD) 325 Broadway, Boulder, Colorado 80305