pppd --version (return code: 0)
pppd version 2.4.7
pppd --help (return code: 0)
pppd version 2.4.7 Usage: pppd [ options ], where options are: <device> Communicate over the named device <speed> Set the baud rate to <speed> <loc>:<rem> Set the local and/or remote interface IP addresses. Either one may be omitted. asyncmap <n> Set the desired async map to hex <n> auth Require authentication from peer connect <p> Invoke shell command <p> to set up the serial line crtscts Use hardware RTS/CTS flow control defaultroute Add default route through interface file <f> Take options from file <f> modem Use modem control lines mru <n> Set MRU value to <n> for negotiation See pppd(8) for more options.