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Diffstat (limited to 'microkernel/mach/task.mdwn')
| -rw-r--r-- | microkernel/mach/task.mdwn | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/microkernel/mach/task.mdwn b/microkernel/mach/task.mdwn new file mode 100644 index 00000000..c03c6a14 --- /dev/null +++ b/microkernel/mach/task.mdwn @@ -0,0 +1,23 @@ +[[!meta copyright="Copyright © 2002, 2003, 2010 Free Software Foundation, +Inc."]] + +[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable +id="license" text="Permission is granted to copy, distribute and/or modify this +document under the terms of the GNU Free Documentation License, Version 1.2 or +any later version published by the Free Software Foundation; with no Invariant +Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license +is included in the section entitled [[GNU Free Documentation +License|/fdl]]."]]"""]] + +A Mach *task* is a collection of resources, a [[virtual_address_space]], and a +[[port name space|port]]. They depend on [[thread]]s for executing program +code: a task alone has no means to do so. + +Switching from one task to another one involves doing a *context switch*, which +is usually not a cheap operation, as it involves switching the hardware's idea +of the memory layout ([[virtual_address_space]]), amongst others. + +Mach tasks are distinct from [[UNIX processes|unix/process]] in that they +provide less facilities. In processes, there are [[unix/signal]]s, process / +group / session IDs, [[unix/file_descriptor]]s and many other things. Tasks +are used for resource allocation and sharing; they are *resource container*s. |