---
name: "zmtrigger.pl"
section: "1"
platform: "linux"
package: "zoneminder"
version: "1.36.35+dfsg1-1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/zmtrigger.pl"
---

# zmtrigger.pl(1)

ZoneMinder External Trigger Script

## NAME

zmtrigger.pl - ZoneMinder External Trigger Script

## DESCRIPTION

This script is used to trigger and cancel alarms from external connections using an arbitrary text based format.

This script offers generic solution to external triggering of alarms. It can handle external connections via either internet socket, unix socket or file/device interfaces. You can either use it 'as is' if you can interface with the existing format, or override connections and channels to customise it to your needs.

If enabled by the OPT\_TRIGGERS option, Zoneminder service start zmtrigger.pl which listens for control messages on TCP port 6802.

## TRIGGER MESSAGE FORMAT

**id**\|**action**\|**score**\|**cause**\|**text**\|**showtext**

- **id**

  ```
    is the id number or name of the ZM monitor.
  ```

- **action**

  ```
    Valid actions are 'on', 'off', 'cancel' or 'show' where
    'on' forces an alarm condition on;
    'off' forces an alarm condition off;
    'cancel' negates the previous 'on' or 'off';
    'show' updates the auxiliary text represented by the %Q
    placeholder, which can optionally be added to the affected monitor's
    timestamp label format.

    Ordinarily you would use 'on' and 'cancel', 'off' would tend to be
    used to suppress motion based events. Additionally 'on' and 'off' can
    take an additional time offset, e.g. on+20 which automatically
    cancel's the previous action after that number of seconds.
  ```

- **score**

  ```
    is the score given to the alarm, usually to indicate it's
    importance. For 'on' triggers it should be non-zero, otherwise it should
    be zero.
  ```

- **cause**

  ```
    is a 32 char max string indicating the reason for, or source of
    the alarm e.g. 'Relay 1 open'. This is saved in the 'Cause' field of the
    event. Ignored for 'off' or 'cancel' messages.
  ```

- **text**

  ```
    is a 256 char max additional info field, which is saved in the
    'Description' field of an event. Ignored for 'off' or 'cancel' messages.
  ```

- **showtext**

  ```
    is up to 32 characters of text that can be displayed in the
    timestamp that is added to images. The 'show' action is designed to
    update this text without affecting alarms but the text is updated, if
    present, for any of the actions. This is designed to allow external input
    to appear on the images captured, for instance temperature or personnel
    identity etc.
  ```

```
  Note that multiple messages can be sent at once and should be LF or CRLF
  delimited. This script is not necessarily intended to be a solution in
  itself, but is intended to be used as 'glue' to help ZoneMinder interface
  with other systems. It will almost certainly require some customisation
  before you can make any use of it. If all you want to do is generate alarms
  from external sources then using the ZoneMinder::SharedMem perl module is
  likely to be easier.
```

## EXAMPLES

```
  3|on+10|1|motion|text|showtext
```

Triggers 'alarm' on camera #3 for 10 seconds with score=1, cause='motion'.