Path: utzoo!attcan!uunet!wyse!mips!prls!philabs!ttidca!mb From: mb@ttidca.TTI.COM (Michael Bloom) Newsgroups: comp.unix.wizards Subject: Re: BSD:sockets::SVID:(what?) Message-ID: <2820@ttidca.TTI.COM> Date: 29 Jun 88 09:52:59 GMT References: <5968@umn-cs.cs.umn.edu> Reply-To: mb@ttidca.tti.com (Michael Bloom) Organization: Citicorp/TTI, Santa Monica Lines: 53 In article <5968@umn-cs.cs.umn.edu> randy@umn-cs.UUCP (Randy Orrison) writes: >For a project I'm working on... > What are the SVID and POSIX eqivalents of sockets in BSD? That's a real good question. For now, SV3 has no *close* equivalents. TCP/IP has been promised for 5.4, but the big (hear this, AT&T?) question is "via what mechanism?" Berkeley recently released a new version of TCP, which SUN has incorporated into SUNOS 4.0 in the same manner as before: Sockets are accessed _in place of_ inodes; not thru, but in place of. You could loosely call the mechanism used "the file descriptor type switch" (f_type and f_ops). In contrast system V networking is done through (tli) library routines which make multiple calls via the inode interface that in turn find their way into the streams code, passing streams messages through multiple modules possibly before even encountering the tcp protocol code. Portions of "the big question are": Will IP/UDP/TCP be rewritten as streams modules? What about the UNIX domain? Alternately, will a stream cap driver be written that provides a tpi interface? If so, perhaps this could co-exist with the current socket level code, to support the vast quantities of existing applications. A question for SUN: Are there plans for 5.4 being able to run binaries compiled to run under SUNOS 4.x? If so, will this result from services provided by SUN's 5.4 being different from those provided by AT&T's 5.4? Will streams itself be different in 5.4? Sun has documented that they had to "extend" streams just to be able to provide a streams terminal driver that could handle the bsd functionality not present in system V tty drivers. Will further "extensions" be necessary (or provided as the new standard) for being able to properly and efficiently support BSD networking? Judging from discussions I've had with people using streams for (non-tcp) networking the answer is probably yes, but it would be useful to hear the official word on this. For future compatibility: Should people *now* writing new protocols that will use IP put stream caps on the bsd protocols? Or should they use the protocol-protocol interface? >Also, do they interface? Can i connect a socket on a BSD system to a snark >on a POSIX system? If you're talking about TCP snarks, you should be able to.