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* [9fans] rfork and nerrlab - I am confused
@ 2010-11-01 20:52 Steve Simon
  2010-11-01 21:17 ` Anthony Martin
  0 siblings, 1 reply; 2+ messages in thread
From: Steve Simon @ 2010-11-01 20:52 UTC (permalink / raw)
  To: 9fans

Hi,

I am trying to understand the implementation of sysrfork() in
/sys/src/9/port/sysproc.c:90.

When the new process is created p->nerrlab is set to zero,
however when sysrfork() returns,as the new process, poperror() is
called will clean up the error stack after the matching waserror()
before the systemcall was dispatched.

This should the (from my reading of it) draw an error from
/sys/src/9/pc/trap.c:739, which doesn't happen.

so, I am wrong about how it works, but how does it?

Am I expected to understand this?

-Steve



^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: [9fans] rfork and nerrlab - I am confused
  2010-11-01 20:52 [9fans] rfork and nerrlab - I am confused Steve Simon
@ 2010-11-01 21:17 ` Anthony Martin
  0 siblings, 0 replies; 2+ messages in thread
From: Anthony Martin @ 2010-11-01 21:17 UTC (permalink / raw)
  To: Fans of the OS Plan 9 from Bell Labs

That code path is for the proc that called rfork(). The
new child proc returns through forkchild().



^ permalink raw reply	[flat|nested] 2+ messages in thread

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2010-11-01 20:52 [9fans] rfork and nerrlab - I am confused Steve Simon
2010-11-01 21:17 ` Anthony Martin

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