Page 488 - Asterisk™: The Future of Telephony

WAIT FOR DIGIT
WAIT FOR DIGIT timeout

Waits up to timeout milliseconds for the channel to receive a DTMF digit. Use -1 for
the timeout value if you want the call to block indefinitely.
Return values:
-1
Error or channel failure
0
Timeout
value
ASCII value of digit (if pressed), in decimal

460 | Appendix C: AGI Reference