rainwatr@ucunix.san.uc.edu (Don Rainwater) (04/11/91)
Well, I'm still looking for a way to 'ping' an internet node from within Hypercard. Someone mentioned the tcp hypercard tools that are available on apple.com (I believe). These xcmds allow you to do a great many things using tcp (open a socket, listen on a socket, etc), but nothing jumped out at me and said 'ping' :-). Am I missing something here? Anyway, if anyone has any information, or can point me in the right direction, I would appreciate it. Thanks.
resnick@cogsci.uiuc.edu (Pete Resnick) (04/11/91)
rainwatr@ucunix.san.uc.edu (Don Rainwater) writes: >Well, I'm still looking for a way to 'ping' an internet node from >within Hypercard. Someone mentioned the tcp hypercard tools that are >available on apple.com (I believe). These xcmds allow you to do a great >many things using tcp (open a socket, listen on a socket, etc), but >nothing jumped out at me and said 'ping' :-). Am I missing something >here? MacTCP does not currently allow you access to ICMP, which is the part of the TCP/IP protocol suite which 'ping' uses. There is some reason to believe that a future release of MacTCP will have such access. As soon as the new version comes out, I will write a desk accessory to do ping myself and put it out on the net. It's a pretty easy program. pr -- Pete Resnick (...so what is a mojo, and why would one be rising?) Graduate assistant - Philosophy Department, Gregory Hall, UIUC System manager - Cognitive Science Group, Beckman Institute, UIUC Internet/ARPAnet/EDUnet : resnick@cogsci.uiuc.edu BITNET (if no other way) : FREE0285@UIUCVMD
dorner@pequod.cso.uiuc.edu (Steve Dorner) (04/11/91)
>available on apple.com (I believe). These xcmds allow you to do a great >many things using tcp (open a socket, listen on a socket, etc), but >nothing jumped out at me and said 'ping' :-). The XCMD's are TCP only. Which hardly matters, since MacTCP won't let you send ICMP packets anyway, so you can't do a ping with MacTCP. You'll have to wait for Apple to add ICMP to MacTCP, or roll your own IP networking software, or buy InterCon's TCP driver, which has ICMP (right?). -- Steve Dorner, U of Illinois Computing Services Office Internet: s-dorner@uiuc.edu UUCP: uunet!uiucuxc!uiuc.edu!s-dorner
kraig@biostr.washington.edu (Kraig Eno) (04/12/91)
rainwatr@ucunix.san.uc.edu (Don Rainwater) writes: > >Well, I'm still looking for a way to 'ping' an internet node from > >within Hypercard. >[Looking at the MacTCP toolkit], nothing jumped out at me and said 'ping'. resnick@cogsci.uiuc.edu (Pete Resnick) responds: >> MacTCP does not currently allow you access to ICMP, which is the >> part of the TCP/IP protocol suite which 'ping' uses. MacTCP lets you send and receive TCP packets on any socket number. I don't know just how ping really works, but if you look at the man page, it says it sends a timestamp over the network which is then echoed by the remote host; when you receive the timestamp again, you can compute the round-trip travel time. Don, this would be trivially easy to do with the "TCP XCMD example" file that you get with the MacTCP toolkit. Simply open port #7 on a Unix box, which is the echo service, and use an idle handler to send it a stream of packets containing "the seconds". The unix host will bounce back whatever it receives. Whenever you get packets back, compute the time it took by comparing the time in the packet with the current time, to get elapsed time in seconds. For sub-second accuracy, you'd have to play a few more tricks, but this will get you started. Anyone with Unix source want to check and see if it uses port 7? Kraig Eno, kraig@biostr.washington.edu "Problems generate new knowledge" - M. Usui
knutsen@pilot.njin.net (Mark Knutsen) (04/12/91)
>resnick@cogsci.uiuc.edu (Pete Resnick) responds: >>> MacTCP does not currently allow you access to ICMP, which is the >>> part of the TCP/IP protocol suite which 'ping' uses. kraig@biostr.washington.edu (Kraig Eno) writes: >MacTCP lets you send and receive TCP packets on any socket number. I >don't know just how ping really works, but if you look at the man page, > ... >Anyone with Unix source [to ping] want to check and see if it uses port 7? Pete Resnick is correct, the standard 'ping' uses ICMP, not TCP. Still, the method Kraig Eno describes is a perfectly fine way to determine if a host is alive. After all, what good is a host if TCP isn't running? :-) -- =============================================================================== Mark Knutsen, now located in New Haven, CT. Same old email address: knutsen@pilot.njin.net OR knutsen@pilot.rutgers.edu OR {...}!rutgers!knutsen