Send a ping via ExternalProcess on an Windows-machine

I need to specify a MAC-Address from an ip-Address. I intend to manage this with a ping on the ip followed by an arp request.

When i test following code

    | aString |
    aString := 'dir c:\'.
    Transcript show: (ExternalProcess new shOne: aString).

i can execute the command in the Windows-Shell and get the directory tree of my HD.

When i try this one, to solve my problem

    | aString |
    aString := 'ping 10.26.64.1'.
    Transcript show: (ExternalProcess new shOne: aString).

the code causes following exception

    'Unhandled exception: Strings only store Characters'

I debugged the code and have no idea how to solve this problem. Maybe anyone can help me.

Cheers,
Harald

At 04:55 AM 7/6/2010, HaJo wrote:

Try this

    | aString |
    aString := 'ping 10.26.64.1'.
    (ExternalProcess new shOne: aString) inspect

to see what you're getting back from the ping.


-cstb


_______________________________________________
vwnc mailing list
[hidden email]
http://lists.cs.uiuc.edu/mailman/listinfo/vwnc

If you fork an external process, you need to know what encoding the result is going to come back as. If you use shOne:, you're getting a Windows shell, and we tell the Windows shell what encoding to use for shell commands - UTF-16, using the /u command-line option. That means you'll get back correct answers for things like directory listings with files that have interesting characters in their name. But if the program in question doesn't honour that, it'll give things back in some other encoding, probably something like CP437. So something more like

WinProcess new fork: 'ping' arguments:  #('10.26.64.1')

would do it. You're getting the wrong encoding in that case, but since your result is likely ascii, it's not wrong enough to make a difference.  Throwing in an "encoding: '437'; " will set it to one that is more likely to be right.

At 06:33 PM 2010-07-08, cstb wrote:

At 04:55 AM 7/6/2010, HaJo wrote:

>I need to specify a MAC-Address from an ip-Address. I intend to manage this
>with a ping on the ip followed by an arp request.
>
>When i test following code
>
>    | aString |
>    aString := 'dir c:\'.
>    Transcript show: (ExternalProcess new shOne: aString).
>
>i can execute the command in the Windows-Shell and get the directory tree of
>my HD.
>
>When i try this one, to solve my problem
>
>    | aString |
>    aString := 'ping 10.26.64.1'.
>    Transcript show: (ExternalProcess new shOne: aString).
>
>the code causes following exception
>
>    'Unhandled exception: Strings only store Characters'

Try this

    | aString |
    aString := 'ping 10.26.64.1'.
    (ExternalProcess new shOne: aString) inspect

to see what you're getting back from the ping.


-cstb


_______________________________________________
vwnc mailing list
[hidden email]
http://lists.cs.uiuc.edu/mailman/listinfo/vwnc

_______________________________________________
vwnc mailing list
[hidden email]
http://lists.cs.uiuc.edu/mailman/listinfo/vwnc

Thank you for your reply,

ExternalProcess new fork: 'ping "127.0.0.1"' does the job.

cheers Harald