mtools: parsing order
3.6 Location of configuration files and parsing order
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The configuration files are parsed in the following order:
1. compiled-in defaults
2. `/etc/mtools.conf'
3. `~/.mtoolsrc'.
4. `$MTOOLSRC' (file pointed by the `MTOOLSRC' environmental variable)
Options described in the later files override those described in the
earlier files. Drives defined in earlier files persist if they are not
overridden in the later files. For instance, drives A and B may be
defined in `/etc/mtools.conf' and drives C and D may be defined in
`~/.mtoolsrc' However, if `~/.mtoolsrc' also defines drive A, this new
description would override the description of drive A in
`/etc/mtools.conf' instead of adding to it. If you want to add a new
description to a drive already described in an earlier file, you need
to use either the `+drive' or `drive+' keyword.