Wireshark · Ethereal-users: Re: [Ethereal-users] Tethereal can, Ethereal cannot

[Jeetendra Singh <jeetendra_singh@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>]

>>Ethereal's opening the pipe in non-blocking mode, but it's not turning
>>non-blocking mode off on the pipe once that completes,

My first question will be "Does tethereal block on pipe?" Apple to apple :)

>>so if it tries
>>reading from the pipe before something opens the pipe for writing, it'll
>>get an EOF and assume that there's nothing more to read.

I am first running "cat packet.pcap > /tmp/myfifo" command before starting Ethereal (the command hangs till a reader<ethereal in my case> is invoked). But ethereal after starting is not able to capture anything.
Even if i do this other way round, Ethereal blocks (not even refreshes the screen) till I run my command to fill "myfifo", so it seems somehow my Ethereal (version 0.10.11) is not working in non-blocking mode.

JFYI, Ethereal does recognise an EOF if my "packet.pcap" file is empty and displays a message saying that EOF has been detected.

Any ideas?
Thanks,
Jeetendra


Guy Harris wrote:

Jeetendra Singh wrote:

but ethereal is not able to display the captured packets. Am using
following command:
    "ethereal -i /tmp/myfifo -kl"
Ethereal just says that theres nothing to display as no data has been
captured.

Ethereal's opening the pipe in non-blocking mode, but it's not turning
non-blocking mode off on the pipe once that completes, so if it tries
reading from the pipe before something opens the pipe for writing, it'll
get an EOF and assume that there's nothing more to read.