TaskManager

Contents

Introduction and Overview

The Task Manager module provides various facilities to ease the management of tasks. These are:

  • a SWI to find the name of a task, given its handle
  • a SWI to enumerate all the currently active tasks
  • a SWI to initiate a desktop shutdown
  • a * Command to change the size of various system areas.

The Task Manager module is not available in RISC OS 2.

SWI calls

TaskManager_TaskNameFromHandle
(SWI &42680)

Finds the name of a task
On entry
R0=task handle
On exit
R0=pointer to task name
Interrupts
Interrupts are undefined
Fast interrupts are enabled
Processor mode
Processor is in SVC mode
Re-entrancy
SWI is re-entrant
Use

This call returns the name of a task, given its task handle. If you wish to keep the name, you must copy it into your own workspace.

Related SWIs
TaskManager_EnumerateTasks

TaskManager_EnumerateTasks
(SWI &42681)

Enumerates all the currently active tasks
On entry
R0=0 for first call, or value from previous call
R1=pointer to word aligned buffer
R2=buffer length (in bytes)
On exit
R0=value to pass to next call, or < 0 if no more entries
R1=pointer to first unused word in buffer
R2=number of unused bytes in buffer
Interrupts
Interrupts are undefined
Fast interrupts are enabled
Processor mode
Processor is in SVC mode
Re-entrancy
SWI is not re-entrant
Use

This call enumerates all the currently active tasks. On exit the buffer is filled with entries of the form:

OffsetContents
+0task handle
+4pointer to task name (should be copied away and not used in place)
+8amount of memory (in K) used by the task
+12flags:
Bit(s)Meaning
0module task, otherwise application task
1slot bar is draggable, otherwise slot bar cannot be dragged
2-3Reserved, must be zero

Related SWIs
TaskManager_TaskNameFromHandle

TaskManager_Shutdown
(SWI &42682)

Initiates a desktop shutdown
On entry
R0=shutdown flags :
Bit(s)Meaning
0don't display restart dialogue (equivalent to Exit menu option)
1don't broadcast Message_PreQuit
2flag in CMOS as portable power-down
3send Message_Shutdown
4reject OS_UpCall 1 and 2 (see OS_UpCall 1 and 2)
5-31Reserved, must be zero
On exit
None
Interrupts
Interrupts are undefined
Fast interrupts are enabled
Processor mode
Processor is in SVC mode
Re-entrancy
SWI is not re-entrant
Use

This call initiates a desktop shutdown. The actions performed are controlled by the shutdown flags held in R0.

Related APIs
None

* Commands

*ChangeDynamicArea

Changes the size of the font cache, system sprite area and/or RAM disc
Syntax
*ChangeDynamicArea [-FontSize <n>[K]] [-SpriteSize <n>[K]] [-RamFSSize <n>[K]]
Parameters
<n>-Size of the area to be set, in kilobytes
Use

*ChangeDynamicArea changes the size of the font cache, system sprite area and/or RAM disc. It generates an error if it is unable to do so. Its main use is in desktop boot files.

Example
*ChangeDynamicArea -SpriteSize 32K -RamFsSize 100K
Related SWIs
OS_ChangeDynamicArea, OS_UpCall 257

Document information

Maintainer(s): RISCOS Ltd <developer@riscos.com>
History:
RevisionDateAuthorChanges
1ROLInitial version
Disclaimer:

Copyright © Pace Micro Technolgy plc, 2002.
Portions copyright © RISCOS Ltd, 2002.
Published by RISCOS Limited.
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