Wimp_StartTask (changes)
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WindowManager
» SWI Calls
» Wimp_StartTask
Wimp_StartTask
(SWI &400DE)
| Entry | |
|---|---|
| R0 | Pointer to *command string |
| Exit | |
|---|---|
| Task handle of child, or | |
| 0 if it has exited |
Use
The purpose of this call is to create a new task and execute the given * command.
Notes
The SWI returns control when the new task exits, or calls Wimp_Poll.
This call can only be used from USR mode with an empty SVC stack, and only when it is the ‘live’ task. i.e gained control from Wimp_Initialise or Wimp_Poll.
It is not sufficient to drop from SVC mode into USR mode to call this SWI, and precludes starting taks from within:
- Callbacks
- Interrupts
- Filters
- SWIs
- Vectors (events, etc…)
- Any other system call mechanism
See also
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