dieter@lynn.cs.ucla.edu (Dieter Rothmeier) (12/02/89)
While reading some code, I came across the following construct: struct sockaddr_in sin; .... sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK); ... I know about INADDR_ANY, but I've never seen this one. It's defined in <netinet/in.h>. I looked through the documentation (this is on a Sun 3/80) quite extensively, but couldn't find anything. Any help would be appreciated. Dieter
mcgrath@paris.Berkeley.EDU (Roland McGrath) (12/02/89)
INADDR_LOOPBACK is 0x7f000001, Internet address 127.0.0.1, usually called `localhost'. Talking to this address gets you back to where you started from, without going through the network hardware. -- Roland McGrath Free Software Foundation, Inc. roland@ai.mit.edu, uunet!ai.mit.edu!roland
housel@en.ecn.purdue.edu (Peter S. Housel) (12/02/89)
In article <MCGRATH.89Dec1142539@paris.Berkeley.EDU>, mcgrath@paris (Roland McGrath) writes: >INADDR_LOOPBACK is 0x7f000001, Internet address 127.0.0.1, usually called >`localhost'. Talking to this address gets you back to where you started from, >without going through the network hardware. The nifty thing is that (on many systems with BSD-derived networking) you can disable the loopback-net, through which address 127.0.0.1 is routed. Running "ifconfig lo0 down" will disable the "loopback interface" and the machine will be unable to talk to itself. We once had cause to do this. Due to some kernel bug, packets were occasionally getting stuck in loops within the loopback. The system would get very sluggish, forwarding packets in tight little circles. Until the problem was fixed we just disabled the "interface" for 30 seconds or so until the offending packet timed out. -Peter S. Housel- housel@ecn.purdue.edu ...!pur-ee!housel