Service_StartWimp (changes)

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Programmer's WindowManager Reference Manuals

» Part 7 - The Desktop?Service Calls

» Service_StartWimpThe Window Manager

Service_StartWimp

(Service Call &49)

Use

This service is broadcast by the Wimp to start up resident module tasks by passing the returned *command to Wimp_StartTask.

Notes

Module tasks which wish to start should claim this service, passing their start *command in R0. The Wimp will re-broadcast this service until no more modules claim it.

Filer module tasks should wait for Service_StartFiler instead.

To prevent infinite loops if an error occurs in starting a task, modules should:

1. set their taskhandle to 0 when initialising, Service_PostReset, or Service_StartedWimp
2. only claim this service if their taskhandle is zero. i.e. they are not already running, and not attempting to restart
3. set their taskhandle to a flag value (-1) when they claim this service
4. set their taskhandle based on the return result of Wimp_Initialise if their command is called, or set their taskhandle back to 0 on Service_StartedWimp
5. set their taskhandle back to 0 when they quit using Wimp_CloseDown

See also

• Service Calls
• Service_PostReset
• Service_StartFiler
• Service_StartedWimp
• Wimp_CloseDown
• Wimp_Initialise
• Wimp_StartTask