I typically start GUI Emacs on macOS, https://bitbucket.org/mituharu/emacs-mac/overview, installed via Nix package manager, as part of a larger startup script on the terminal (iterm). While Emacs is loading I am entering passwords to decrypt various encfs volumes. Annoyingly, Emacs steals focus after a while, sometimes in the middle of entering a password on the terminal. I am aware of about when in the startup sequence this happens so I can simply wait for it to complete then switch focus back to terminal, but naturally I prefer to avoid this.
I've searched for all occurrances of raise-frame, select-frame-set-input-focus, x-focus-frame, select-frame and while there are many instances of these they are not at top-level. To some of these few containing functions that I wondered may be getting called during init, I added message printf style statements, restarted Emacs and read the *Messages* buffer, none of these were printed out. I might have missed something though as I didn't try them all this way, just the most likely looking ones.
It may be a feature of the Emacs I use and I may have to patch to overcome, but I don't want to have to do that.
Any clues what I should look for to change this behavior?
select-frame-set-input-focusand other functions that may exist along those lines are what causes Emacs to acquire focus on OSX 10.6.8. I have no experience with higher versions of OSX or MacOS, but assume they may be the same. At all locations in the Lisp functions that I use daily, I have changedselect-frame-set-input-foucstoselect-frameandraise-frame. The most common annoyance for me was sending and receiving email with Wanderlust -- I generally like to use other applications at that time. I have not traced the startup without any user-config...startup.elis baked into the Emacs executable during the build process. I use a custom version ofstartup.el, primarily because the stock version messed too much with how windows / buffers are displayed when Emacs starts. If you build your own Emacs from source and are sufficiently motivated, then you may wish to have a look at the existingstartup.eland see if certain custom modifications have the desired effect. .... The offending code may be elsewhere (i.e., I use the vanilla Emacs for OSX/MacOS, not Mituharu's port), butstartup.elmay be a good place to start looking.