Based on the Gentoo wiki ---> wpa_supplicant ---> the diff page of gitweb,
the -M option(CONFIG_MATCH_IFACE option) are used to descirbe matching rules
with a wildcard interface name.
But the description doesn't appear in the wpa_supplicant wiki page and relevant
pages clearly, which makes some confuse to those who are not familiar with these
Advice: I think it's maybe better to add the description of -M option to the wpa_
suppliant wiki page(using things like "Tips" or "Comment" at the beginning of the
page),wpa_supplicant manual page and wpa_supplicant.conf manual page.
The main namespace of our wiki is publicly modifiable. This content can be added by your (or anyone who is interested). Our devs are busy enough, so this is a WONTFIX from the wiki team... That stated, it looks like someone (perhaps the creator of this bug?) did note the option in this change:
If there is something else missing you think is missing from this page, kindly create an account and add it: