$ wpa_supplicant
usage:
wpa_supplicant [-BddhKLqqstuvW] [-P<pid file>] [-g<global ctrl>] \
[-G<group>] \
-i<ifname> -c<config file> [-C<ctrl>] [-D<driver>] [-p<driver_param>] \
[-b<br_ifname>] [-e<entropy file>] [-f<debug file>] \
[-o<override driver>] [-O<override ctrl>] \
[-N -i<ifname> -c<conf> [-C<ctrl>] [-D<driver>] \
[-m<P2P Device config file>] \
[-p<driver_param>] [-b<br_ifname>] [-I<config file>] ...]
So please change the man page:
<wpa_supplicant [ -BddfhKLqqsTtuvW ] [ -iifname ] [ -cconfig file ] [ -Ddriver ] [ -PPID_file ] [ -foutput file ]
Because -c and -i are not "optional" but required.
By the way you say -PPID_file so say -cconfig_file not -cconfig file.
Also e.g., -c config_file looks smarter than -cconfig_file and works
too! So maybe add that space after all of them.