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WaitForSilence()

Synopsis

Waits for a specified amount of silence.

Description

Waits for up to silencerequired milliseconds of silence, iterations times. An optional timeout specified the number of seconds to return after, even if we do not receive the specified amount of silence. Use timeout with caution, as it may defeat the purpose of this application, which is to wait indefinitely until silence is detected on the line. This is particularly useful for reverse-911-type call broadcast applications where you need to wait for an answering machine to complete its spiel before playing a message.

Typically you will want to include two or more calls to WaitForSilence when dealing with an answering machine; first waiting for the spiel to finish, then waiting for the beep, etc.

Example: Wait for half a second of silence, twice
same => n,WaitForSilence(500,2)
Example: Wait for one second of silence, once
same => n,WaitForSilence(1000)
Example: Wait for 300 ms of silence, 3 times, and returns after 10 seconds, even if no silence detected
same => n,WaitForSilence(300,3,10)
Sets the channel variable WAITSTATUS to one of these values:

  • WAITSTATUS

    • SILENCE - if exited with silence detected.

    • TIMEOUT - if exited without silence detected after timeout.

Syntax

WaitForSilence([silencerequired,[iterations,[timeout]]])
Arguments

  • silencerequired - If not specified, defaults to '1000' milliseconds.

  • iterations - If not specified, defaults to '1'.

  • timeout - Is specified only to avoid an infinite loop in cases where silence is never achieved.

See Also

Generated Version

This documentation was generated from Asterisk branch 21 using version GIT