| role | default setting prio | location | presence | remarks + |
|---|---|---|---|---|
| internal + | 100 + | (compiled into the executable) + | always + | the ultimate fallback; allows pcb-rnd even if no other configuration file is found + + + |
| system + | 200 + | /usr/share/pcb-rnd/pcb-conf.lht + | recommended + | should hold system and installation specific settigns, e.g. path to the system-wise installed footprint library + + |
| user + | 300 + | ~/.pcb-rnd/pcb-conf.lht + | recommended + | store user preferences, user's common footprint lib path, etc; this is the first file the user can modify (even from the GUI) + + |
| environment + | 400 + | environment variables (TODO) + | occassional + | inject the same (temporary) settings in multiple pcb-rnd sessions without having to change config files + + |
| project + | 500 + | projdect.lht in the project directory + | optional + | local project settings - useful for large projects with multiple design (.pcb) files + + |
| design + | 600 + | saved in the design (.pcb) file + | optional, common + | per design deviation from the user+system config + + |
| cli + | 700 + | command line argument + | occassional + | inject/change a setting for a single session; useful in batch/automated processing + |
+Pcb-rnd reads them all, then merges all settings into a master binary +representation. If a setting is specified in multiple sources, the one +with the higher priority wins, except for lists where it is also possible +to prepend/append items. Default priorities are designed to result +precedence in an intuitive way (e.g. design settigns overwrite user settings). +However, priority can be changed per setting, resulting +in weak settings ("use this value if it was not already set") or strong settings +("I always want to use mincut, so I enable it from my user's config with high +priority and a version controlled project setting can not turn it off") + +