Messages in this thread | | | Date | Sat, 10 Jan 2009 23:31:30 +0100 | From | Oleg Nesterov <> | Subject | Re: [RESEND][RFC PATCH v2] waitfd |
| |
On 01/10, Casey Dahlin wrote: > > Scott James Remnant wrote: >> On Wed, 2009-01-07 at 18:19 +0100, Oleg Nesterov wrote: >> >>> Please note that unlike other sys_...fd() syscalls, sys_waitfd() >>> doesn't allow to pass O_CLOEXEC. Looks like we need a separate >>> "flags" argument... >>> >>> Also, ioctl(FIONBIO) or fcntl(O_NONBLOCK) have no effect on >>> waitfd, not very good. >>> >>> I'd suggest to remove WNOHANG from waitfd_ctx->ops and treat >>> (->f_flags & O_NONBLOCK) as WNOHANG. >>> >>> (can't resist, ->ops is not the best name ;) >>> >>> >> Definitely agree here, waitfd() doesn't need WNOHANG - we already have >> ONONBLOCK. >> >> That also solves one of the strangest behaves of waitid when you use >> WNOHANG (it returns zero and you have to check whether it changed the >> struct), now you just read() - if no child you get EAGAIN, if a child >> you read a struct. >> > From the perspective of waitfd, the only difference between WNOHANG and > O_NONBLOCK is which argument you put the flags in.
No. Please see the note about ioctl/fcntl above.
Oleg.
| |