vm(1) VoiceModem is the program for handling the voice modem functionality from shell scripts

ACTIONS

beep options [<frequency [<length in 0.001sec>]]>
diagnostics options device name (e.g. ttyS2
dial options phone number
help
play options [<file names]+>
record options file name
shell options [<shell script [shell options]]>
wait options [<time in seconds]>
devicetest

OPTIONS

-c n use compression type n
-d n set i/o device
-t, -m, -i, -e, -s, -H equals to -d <2,3,4,5,6,7>
-l s set device string (e.g. -l ttyS2:ttyC0)
-v verbose output
-w use off / on hook signal from local handset to start and stop recording
-x n set debug level
-L n set maximum recording length in sec
-P print first DTMF tone on stdout and exit
-R read and print DTMF string on stdout and exit
-S s set default shell for shell scripts (e.g. -S /bin/sh)
-T n set silence timeout in 0.1sec
-V n set silence threshold to <n> (0-100%%)