The simplest Linux config files typically have formats that look something like this:
# how often (in minutes) data is saved when all interface are offline
OfflineSaveInterval 30
# force data save when interface status changes (1 = enabled, 0 = disabled)
SaveOnStatusChange 1
# file used for logging if UseLogging is set to 1
LogFile "/var/log/vnstat.log"
# file used as daemon pid / lock file
PidFile "/var/run/vnstat.pid"The standard extension, if there is one, is .conf. Hash (#) is the most common comment character by far. Semicolon and C-style comments crop up too.
I think a good, human-manipulatable config file that ISN’T part of the wallet would be a big step forward. There are a lot of options that are currently specified on the command line (noirc, for example, or -minimizetotray) which might be better specified in a config file.