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Ethereal-dev: Re: [Ethereal-dev] Reading a capture file from stdin is really working?!?

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From: Ulf Lamping <ulf.lamping@xxxxxx>
Date: Sat, 07 Jan 2006 23:28:40 +0100
Guy Harris wrote:

LEGO wrote:

Isn't that it is exactly how it should work?
 -r for random access

... which doesn't work with pipes.

 -i for sequential access.

... which only works with libpcap files.

Tethereal *itself* doesn't need random access. It's Wiretap that needs it, to handle the checks to figure out what type of file it's reading.

If we did our own buffering in Wiretap (in addition to, or instead of, the buffering done by the "standard I/O library" routines), and arranged that seeks *within* a buffer were done by using existing stuff in the buffer, then, with a sufficiently large buffer, we could probably support reading sequentially from a pipe. The buffer might have to be relatively big, for the heuristic file readers, which might have to read a significant amount of the file to be sure of the type, and for the libpcap reader, which has to determine which of various flavors of libpcap, sharing the same magic number, the file is.

Thanks for all replys,

the way I recognized it is exactly as intended.

Regards, ULFL