Subject: Re: default maximum number of open file descriptors too small?
To: Ty Sarna <>
From: Jason Thorpe <>
List: tech-kern
Date: 11/30/1995 22:38:23
On Thu, 30 Nov 1995 04:05:01 GMT (Ty Sarna) wrote:

 > If it does look doable, before tackiling the kernel you could do this as
 > a proof-of-concept: start by implementing upoll() as a user-space
 > wrapper on select(), and the poll() on top of it.  This will be useful
 > in porting NetBSD code to other OSes which have select() but not
 > poll(), if NetBSD is converted.  Then implement select() as a wrapper on
 > upoll(), which will definately be needed if NetBSD converts.  Then put
 > the emulated-select()-on-emulated-upoll()-on-syscall-select() in your
 > libc and run your system this way for a while.  That way you can get
 > all the bugs ironed out of the userspace, and even get a start on
 > converting NetBSD's userspace, all before the kernel is touched.

Funny you mention this ... about a year ago, I was porting a SVR4 
application to NetBSD, and it was easier to write a simple poll() as a 
wrapper around select() than to modify the code (about 70 files) to use 
select().  I sent the files poll.c and poll.3 to JT for inclusion in 
libcompat, but nothing ever became of them.  I still have them, and maybe 
I should send them to him again :-)

Jason R. Thorpe                             
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