Compress stream before writing to disk

[jmakov]

This option would allow you to pipe captured stream and process it in-line, before saving it to a file. A use case is saving disk bandwidth using a fast compressor e.g. snappy before saving (from the-tcpdump-group/tcpdump#458).

[mcr]

Since there is a pull request, I am closing this issue, such that we track it there.

[jmakov]

Tracked here: the-tcpdump-group/tcpdump#458