2-speed spindle configuration - help

sudo apt-get install build-essential

ls
autosave.halscope  Documents  linuxcnc  Pictures  Templates
Desktop            Downloads  Music     Public    Videos
cnc@cnc:~$ cd linuxcnc
cnc@cnc:~/linuxcnc$ ls
configs  nc_files
cnc@cnc:~/linuxcnc$ cd configs
cnc@cnc:~/linuxcnc/configs$ ls
vturn_410  vturn_410.pncconf
cnc@cnc:~/linuxcnc/configs$ cd vturn_410
cnc@cnc:~/linuxcnc/configs/vturn_410$ ls
backups          custom_postgui.hal  gvcp-panel.ui          vturn_410.hal
custom.clp       gearchange.comp     postgui_call_list.hal  vturn_410.ini
custom_gvcp.hal  gvcp_call_list.hal  shutdown.hal
custom.hal       gvcp_options.hal    tool.tbl
cnc@cnc:~/linuxcnc/configs/vturn_410$  halcompile --install gearchange.comp
Compiling realtime gearchange.c
Linking gearchange.so
cp gearchange.so /usr/lib/linuxcnc/modules/
cp: cannot create regular file '/usr/lib/linuxcnc/modules/gearchange.so': Permission denied
make: *** [/usr/share/linuxcnc/Makefile.modinc:105: install] Error 1

cnc@cnc:~/linuxcnc/configs/vturn_410$ sudo halcompile --install gearchange.comp

Component

    When we talked about hardware design, we referred to the individual pieces as parts, building blocks, black boxes, etc. The HAL equivalent is a component or HAL component. (This document uses HAL component when there is likely to be confusion with other kinds of components, but normally just uses component.) A HAL component is a piece of software with well-defined inputs, outputs, and behavior, that can be installed and interconnected as needed.

if(spindle_rpm_mode){
     //some code;
 }
else{
   if(spindle_css_mode){
      //some code;
     }
    else{
      //error code;
      //exit;
   }
 }