jc@minya.UUCP (John Chambers) (11/26/90)
Just recently, it came to my attention that at least one commercial version of Unix has a driver that implements a very useful feature: It creates a pseudo-interface that has an IP address, and is a file that can be opened by a process. Thus one can write a program that tells the kernel "If you get any traffic for a.b.c.d, give it to me and I'll handle it." I can think of lots & lots of uses for this. This driver is on Ultrix; it is unsupported, but it is available. Do any other extant Unix releases implement this capability? If so, can you say what they are, what sort of special hooks (if any) are needed, and whether programming examples are available? It's not obvious that this requires a special driver, but I suspect that in most cases it will. You'd think you could do it via a raw socket, for instance, but just try... (If anyone knows how, I'd like to see the code.) I wonder if the Ultrix driver would work on many other Unices. It also seems that a streams-based system should be able to do this, but I haven't yet succeeded in decrypting the manuals, so I can't say for sure. Anyone know for sure? -- Zippy-Says: Imagine ... a world without clothing folds, chiaroscuro, or marital difficulties ... Home: 1-617-484-6393 Work: 1-508-952-3274 Uucp: ...!{harvard.edu,ima.com,eddie.mit.edu,ora.com}!minya!jc (John Chambers) Uucp-map: minya adelie(DEAD)