Save subroutine file and location

Are subroutine files only saved at /linuxcnc/nc_files/ngcgui_lib/utilitysubs ?  I'm the superuser and tried to save a ~Documents subroutine .ngc file to /utilitysubs via command line prompt and denied.  Here's the syntax used.  sudo cp o123.ngc /utilitysub .  mv was used instead of cp and that didn't work either.  Where is a subroutine saved and convention syntax?

Yes, that'd of been the expected but it seems that Debian /utilitysubs isn't being accepted as a file or directory but /utilitysubs icon is clearly a folder, opens, reveals .ngc subprogram files and they open. Could unable to copy an .ngc file to /utilitysubs have something to do with /utiilitysubs root or a permission setting? I thought in the past a subroutine was call able without altering it path, thus, default /utilitysubs.

My primary operating system is Ubuntu and Debian boot able via SD micro. Debian doesn't seem to have an extensive search and Ubuntu Nautilus search would probably need to get used to find an RS-274, PATH and subroutine file to modify it directory.

Thanks for the link.  I did find rs274ngc.inc at the Ubuntu /media and name search.  I'll try to name a new subroutine folder at /linuxcnc or /nc_files  and update the path with permission setting in the Terminal.  3.Library Locations looks like file rs274ngc.inc .  www.linuxcnc.org/docs/html/gui/ngcgui.html

I went to rs274ngc.inc and opened terminal and copied directory sudo -i to root. Pasted rs274ngc.inc directory. chown -v username rs274.inc . Opened rs274ngc.inc and at SUBROUTINE PATH = added text home/username/linuxcnc/subprogram and saved. Pasted subroutine 111.ngc at /subprogram. Axis lathe screen and opened main program including o111 call and pop-up box G-Code error in main program: Unable to open file <111>. I tried changing the subroutine parameter name with angle brackets and receive the same pop-up box error. Could the subroutine path still be incorrect? Could file rs274ngc.inc chown need to go back to read only? Can subroutines be ran when Axis a simulation and is a setting to enable subroutine?