Date: Wed, 26 Jan 2000 02:52:48 +0800 From: Peter Wemm <peter@netplex.com.au> To: "Brian D. Moffet" <brianm@moffetimages.com> Cc: freebsd-hackers@freebsd.org Subject: Re: Performance issue with rfork() and single socketpairs versus multiple socketpairs. Message-ID: <20000125185248.422721C03@overcee.netplex.com.au> In-Reply-To: Message from "Brian D. Moffet" <brianm@moffetimages.com> of "Tue, 25 Jan 2000 09:12:31 PST." <200001251712.JAA41726@moffetimages.com>
next in thread | previous in thread | raw e-mail | index | archive | help
"Brian D. Moffet" wrote: > Okay, stupid question. socketpair returns 2 sockets which according to > the man page are "indistinguishable". Does this mean that you can read and > write to either socket pair? Yep, you can write to either end and it will come out the other end. > pipe(2) returns 2 file descriptors, one of which is a read and one of > which is a write fd. The other end flips these around, and data is not > mixed up that way. One program cannot read and write to the same > file descriptor, with the expectation that the two ends of the pipe will > be able to properly communicate. pipe(2) works the same way as socketpair on FreeBSD. As it does on SVR4 boxes (since 1989, including SCO Unixware and I believe Solaris). > Will socketpair allow one program to read and write to the same file > descriptor (what I would call real "bi-directional")... Like you can do > with a normal old socket? Yes. socketpair(2) and pipe(2) are fully bidirectional. pipe(2) happens to be a lot faster than the sockets based ones. > Thanks > Brian > > > > Use 'pipe(2)' rahter than 'socketpair(2)' as both are bidirectional and > > > pipe is a LOT faster. > > > > Although pipe(2)'s bi-directional capabilities are not standard (I've > > been stung by this in the past :-() > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-hackers" in the body of the message > > Cheers, -Peter -- Peter Wemm - peter@FreeBSD.org; peter@yahoo-inc.com; peter@netplex.com.au "All of this is for nothing if we don't go to the stars" - JMS/B5 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20000125185248.422721C03>