Subject: Re: new vfork(2) implementation
To: Christos Zoulas <christos@zoulas.com>
From: Jason Thorpe <thorpej@nas.nasa.gov>
List: current-users
Date: 01/03/1998 21:00:31
On Sun, 4 Jan 1998 04:43:30 GMT 
 christos@zoulas.com (Christos Zoulas) wrote:

 > (4) If we change any of the file descriptors, we will need to restore
 >     them to what the parent expects.

This is only partially true.  The kernel file descriptors are NOT shared
(that's a different change I'm about to make :-).  Any variables changed
in the child will of course change in the parent, but if the child opens
a file, that file will NOT be open in the parent.

 > (5) Do any of the ports keep the signal info in user space? Because if
 >     they do, signal handlers will need to be saved and restored too.

No, they are currently kept in the u-area on all ports.  I have a large
set of changes that move them into a malloc'd area that is hung off the
proc structure, because I wanted to be able to manipulate them if the
process was swapped out, but some other signal changes were put in, and
I'd have to re-integrate them :-)

Jason R. Thorpe                                       thorpej@nas.nasa.gov
NASA Ames Research Center                            Home: +1 408 866 1912
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