Assuming you're running on Linux (launching with a shell-script?) then you can get *most of* the command line flags two ways:
1) ./fs2_open_3.6.17 --help
2) ./fs2_open_3.6.17 -get_flags, then open flags.lch (should be in your current working dir) in a hex editor (this option should work on all platforms)
However, neither option gives you the flags which accept parameters. The wiki has
a page, however I'm not sure if it's up to date for the BP builds. The -shadow_quality flag (if I got the spelling right) seems to be missing at least...
So, lots of info, but I don't know if I've really answered your question or not
