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Hello,
what happens if IPC uses an invalid thread-id? Is the message although forwarded to the subsystem's chief?
Ciao, Chris -- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Christian Stueble............stueble@ls6.cs.uni-dortmund.de PubKey[BF7104F5].......fp=8678C5D3CAD9CD8C F1DDB8EC202F116A
To be or not to be is true... (apocrypha of George Boole) -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
"CS" == Christian Stueble stueble@amaunet.cs.uni-dortmund.de writes:
CS> what happens if IPC uses an invalid thread-id? Is the message although CS> forwarded to the subsystem's chief?
On MIPS the IPC will fail with "invalid destination". According to my reading of the manual, that is the expected behaviour. Delivery to a chief doesn't make sense, as the "nearest chief" is undefined for a non-existing thread.
Gernot -- Gernot Heiser ,--_|\ School of Computer Sci. & Engin. Phone: +61 2 9385 5156 / \ The University of NSW Fax: +61 2 9385 5533 _,--._* Sydney, Australia 2052 E-mail: gernot@unsw.edu.au v http://www.cse.unsw.edu.au/~gernot PGP fingerprint: 94 1E B8 28 25 FD 7C 94 20 10 92 E5 0B FF 39 8F
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Am Fre, 03 Mär 2000 schrieben Sie:
"CS" == Christian Stueble stueble@amaunet.cs.uni-dortmund.de writes:
CS> what happens if IPC uses an invalid thread-id? Is the message although CS> forwarded to the subsystem's chief?
On MIPS the IPC will fail with "invalid destination". According to my reading of the manual, that is the expected behaviour. Delivery to a chief doesn't make sense, as the "nearest chief" is undefined for a non-existing thread.
Yes, "nearest chief" of the receiver doesn't make sense, but "nearest chief" of the sender does. Does Fiasco behave the same?
The advantage would be that a chief can provide only locally valid thread-ids to its clan and translate them internally into valid thread-ids. To emulate this behaviour currently I have to create a dummy task to prevent invalid thread-ids.
Chris -- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Christian Stueble............stueble@ls6.cs.uni-dortmund.de PubKey[BF7104F5].......fp=8678C5D3CAD9CD8C F1DDB8EC202F116A
To be or not to be is true... (apocrypha of George Boole) -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
"CS" == Christian Stueble stueble@amaunet.cs.uni-dortmund.de writes:
On MIPS the IPC will fail with "invalid destination". According to my reading of the manual, that is the expected behaviour. Delivery to a chief doesn't make sense, as the "nearest chief" is undefined for a non-existing thread.
CS> Yes, "nearest chief" of the receiver doesn't make sense, but "nearest chief" CS> of the sender does.
No. The definition of "nearest chief" involves the relative locations of both, sender and receiver in the task hierarchy. The "nearest chief" may be a member of the sender's clan. See the manual for id_nearest().
Gernot -- Gernot Heiser ,--_|\ School of Computer Sci. & Engin. Phone: +61 2 9385 5156 / \ The University of NSW Fax: +61 2 9385 5533 _,--._* Sydney, Australia 2052 E-mail: gernot@unsw.edu.au v http://www.cse.unsw.edu.au/~gernot PGP fingerprint: 94 1E B8 28 25 FD 7C 94 20 10 92 E5 0B FF 39 8F
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