Execution Status

Every operation reports its outcome on two nodes beside it: output/status-code for your program, and output/status-text for a person.

Status codes

Code Meaning When it happens

Code	Meaning	When it happens
`0`	Idle	The operation has not run since the application started
`1`	OK	The operation completed. A search may still have found nothing - that is a normal result, not an error
`-1`	Busy	Another operation of the same module was still running. Nothing was done; try again when it has finished
`-2`	Invalid input	An input value cannot be used - a required node left empty, an unknown match mode, an image address pointing at this application itself, or a directory path that is absolute or points outside the configuration directory
`-3`	Image read failed	The image node at the given address is missing, empty, inconsistent, or uses an unsupported pixel format. Check that the camera application is running and has captured an image
`-4`	Source not found	The template directory or the template file is missing or unreadable. Check the name against `system/templates`, and check `system/template-dir`: all modules share one template directory
`-5`	Invalid crop region	The region of interest does not fit inside the image. The message names the actual image size
`-6`	Write failed	A file could not be written - usually a permission problem or a full disk
`-7`	Algorithm failed	The matching itself failed
`-8`	Publish failed	The result could not be written back to the Data Layer
`-9`	Module not found	The named module does not exist. Check `system/modules` for the current list
`-10`	Module already exists	A module with that name is already there
`-11`	Licence unavailable	No licence covers the module. See Module Management

0

Idle

The operation has not run since the application started

1

The operation completed. A search may still have found nothing - that is a normal result, not an error

-1

Busy

Another operation of the same module was still running. Nothing was done; try again when it has finished

-2

Invalid input

An input value cannot be used - a required node left empty, an unknown match mode, an image address pointing at this application itself, or a directory path that is absolute or points outside the configuration directory

-3

Image read failed

The image node at the given address is missing, empty, inconsistent, or uses an unsupported pixel format. Check that the camera application is running and has captured an image

-4

Source not found

The template directory or the template file is missing or unreadable. Check the name against system/templates, and check system/template-dir: all modules share one template directory

-5

Invalid crop region

The region of interest does not fit inside the image. The message names the actual image size

-6

Write failed

A file could not be written - usually a permission problem or a full disk

-7

Algorithm failed

The matching itself failed

-8

Publish failed

The result could not be written back to the Data Layer

-9

Module not found

The named module does not exist. Check system/modules for the current list

-10

Module already exists

A module with that name is already there

-11

Licence unavailable

No licence covers the module. See Module Management

These codes are the finders' own execution status, not the module status codes of the Cam Driver or AI Object Matching: -5 here means an invalid crop region. See Execution status of the finders.

These numbers are part of the application’s interface. New codes may be added in later releases, but existing ones never change meaning, so logic written against them keeps working after an update.

This is also why checking the sign is the more robust test: status-code < 0 stays correct even when a release introduces a failure your program has never seen.

Which operation reports which

Operation Possible codes

Operation	Possible codes
Finding a template	`1`, `-1`, `-2`, `-3`, `-4`, `-7`, `-8`
Creating a template	`1`, `-1`, `-2`, `-3`, `-5`, `-6`
`system/save-module-inputs`	`1`, `-6`, `-9`

Finding a template

1, -1, -2, -3, -4, -7, -8

Creating a template

1, -1, -2, -3, -5, -6

system/save-module-inputs

1, -6, -9

Status text

output/status-text always starts with ok: or error: and gives the reason in words. It is written at the same time as the status code, so both always agree.

Each operation has its own pair of nodes, and they keep their values until that operation runs again. A failed template creation therefore does not disturb the result of the last search.