D.11. CHANNEL()

CHANNEL(Feld)
Liest/setzt bestimmte Kanaldaten. Feld ist eines der folgenden (wenn nicht anders angegeben, ist nur Lesen möglich):
audioreadformat
Das Format eingehender Audiodaten auf dem Kanal
audionativeformat
Das native Audioformat des Kanals
audiowriteformat
Das Format ausgehender Audiodaten auf dem Kanal
callgroup
In Asterisk lassen sich Extensions in Call Groups von 0 bis 63 einordnen, z. B. als Kundennummer.[222]
channeltype
Die „Technologie“ dieses Kanals, also z. B. IAX oder SIP
language
Die Sprache für Voice-Prompts. (Sie kann hier auch angegeben werden.)
musicclass
Die Musik-Klasse für Wartemusik, wie in musiconhold.conf definiert. (Sie kann hier auch angegeben werden.)
state
Zustand des Kanals (Down, Rsrvd, OffHook, Dialing, Ring, Ringing, Up, Busy, Dialing Offhook, Pre-ring, Unknown)
tonezone
Die „Tone zone“ bestimmt die Ton-Signale (Wählen, Klingeln, Besetzt, ...) für bestimmte Länder. Sie wird in der Konfigurationsdatei des Kanals (z. B. zaptel.conf) durch loadzone und defaultzone festgelegt. Die möglichen Werte sind (wie in der indications.conf definiert): at, au, be, br, ch, cl, cn, cz, de, dk, ee, es, fi, fr, gr, hu, it, lt, mx, ml, no, nz, pl, pt, ru, se, sg, uk, us, us-old, tw, ve, za.
videonativeformat
Das native Videoformat dieses Kanals
Zusätzlich zu diesen Feldern kann der Treiber des Kanals noch weitere bereitstellen, die man in der entsprechenden Dokumentation nachschlagen kann. Felder, die auf dem aktuellen Kanal nicht zur Verfügung stehen, geben einen leeren String zurück.
; Typ des Kanals abfragen:
exten => 123,1,Set(foo=${CHANNEL(channeltype)})

; Sprache auf Englisch setzen:
exten => 123,1,Set(CHANNEL(language)=en)
Asterisk-Versionen:
        |     |        | 1.4 |————————| 1.6 |————————
Interner Hilfetext zu dieser Funktion in Asterisk 1.4:
  -= Info about function 'CHANNEL' =-

[Syntax]
CHANNEL(item)

[Synopsis]
Gets/sets various pieces of information about the channel.

[Description]
Gets/set various pieces of information about the channel.
Standard items (provided by all channel technologies) are:
R/O     audioreadformat    format currently being read
R/O     audionativeformat  format used natively for audio
R/O     audiowriteformat   format currently being written
R/W     callgroup          call groups for call pickup
R/O     channeltype        technology used for channel
R/W     language           language for sounds played
R/W     musicclass         class (from musiconhold.conf) for hold music
R/W     rxgain             set rxgain level on channel drivers that support it
R/O     state              state for channel
R/W     tonezone           zone for indications played
R/W     txgain             set txgain level on channel drivers that support it
R/O     videonativeformat  format used natively for video

chan_sip provides the following additional options:
R/O    rtpqos             Get QOS information about the RTP stream
       This option takes two additional arguments:
  Argument 1:
    audio                 Get data about the audio stream
    video                 Get data about the video stream
  Argument 2:
    local_ssrc            Local SSRC (stream ID)
    local_lostpackets     Local lost packets
    local_jitter          Local calculated jitter
    local_count           Number of received packets
    remote_ssrc           Remote SSRC (stream ID)
    remote_lostpackets    Remote lost packets
    remote_jitter         Remote reported jitter
    remote_count          Number of transmitted packets
    rtt                   Round trip time
    all                   All statistics (in a form suited to logging, but not for parsing)

Additional items may be available from the channel driver providing
the channel; see its documentation for details.

Any item requested that is not available on the current channel will
return an empty string.
Differenz des internen Hilfetexts von Asterisk 1.2 zu 1.4:
— in Asterisk 1.2 nicht vorhanden —
Differenz des internen Hilfetexts von Asterisk 1.4 zu 1.6:
--- in Asterisk 1.4
+++ in Asterisk 1.6
@@ -16,6 +16,7 @@
   R/O     channeltype        technology used for channel
   R/W     language           language for sounds played
   R/W     musicclass         class (from musiconhold.conf) for hold music
+  R/W     parkinglot         parkinglot for parking
   R/W     rxgain             set rxgain level on channel drivers that support it
   R/O     state              state for channel
   R/W     tonezone           zone for indications played
@@ -23,22 +24,52 @@
   R/O     videonativeformat  format used natively for video

   chan_sip provides the following additional options:
+  R/O    peerip             Get the IP address of the peer
+  R/O    recvip             Get the source IP address of the peer
+  R/O    from               Get the URI from the From: header
+  R/O    uri                Get the URI from the Contact: header
+  R/O    useragent          Get the useragent
+  R/O    peername           Get the name of the peer
+  R/O    t38passthrough     1 if T38 is offered or enabled in this channel, otherwise 0
   R/O    rtpqos             Get QOS information about the RTP stream
          This option takes two additional arguments:
     Argument 1:
       audio                 Get data about the audio stream
       video                 Get data about the video stream
+      text                  Get data about the text stream
     Argument 2:
       local_ssrc            Local SSRC (stream ID)
       local_lostpackets     Local lost packets
       local_jitter          Local calculated jitter
+      local_maxjitter       Local calculated jitter (maximum)
+      local_minjitter       Local calculated jitter (minimum)
+      local_normdevjitter   Local calculated jitter (normal deviation)
+      local_stdevjitter     Local calculated jitter (standard deviation)
       local_count           Number of received packets
       remote_ssrc           Remote SSRC (stream ID)
       remote_lostpackets    Remote lost packets
       remote_jitter         Remote reported jitter
+      remote_maxjitter      Remote calculated jitter (maximum)
+      remote_minjitter      Remote calculated jitter (minimum)
+      remote_normdevjitter  Remote calculated jitter (normal deviation)
+      remote_stdevjitter    Remote calculated jitter (standard deviation)
       remote_count          Number of transmitted packets
       rtt                   Round trip time
+      maxrtt                Round trip time (maximum)
+      minrtt                Round trip time (minimum)
+      normdevrtt            Round trip time (normal deviation)
+      stdevrtt              Round trip time (standard deviation)
       all                   All statistics (in a form suited to logging, but not for parsing)
+  R/O    rtpdest            Get remote RTP destination information
+         This option takes one additional argument:
+    Argument 1:
+      audio                 Get audio destination
+      video                 Get video destination
+
+  chan_iax2 provides the following additional options:
+  R/W    osptoken           Get or set the OSP token information for a call
+  R/O    peerip             Get the peer's ip address
+  R/O    peername           Get the peer's username

   Additional items may be available from the channel driver providing
   the channel; see its documentation for details.

Diese Beschränkung auf 64 Gruppen scheint rein willkürlich zu sein und dürfte für den ein oder anderen Anwender nicht ausreichen.