Eelco Chaudron <[email protected]> writes: > On 3 Sep 2025, at 16:26, Aaron Conole via dev wrote: > >> There is some confusion about which options can be passed to ovs-tcpdump >> when gathering data. The interpretation sometimes is that ovs-tcpdump >> only accepts a specific small set of options and discards other options. >> This leads to questions such as, "How can I use '-C' or set the snaplen >> with ovs-tcpdump like tcpdump allows?" To correct this, print the >> dump_cmd help after the ovs-tcpdump options. >> >> As part of this rework, we delay printing the usage data until after >> all arguments are processed, which allows setting the dumpcmd as well >> for the --help option. >> >> Signed-off-by: Aaron Conole <[email protected]> > > Hi Aaron, > > I think the patch in general is good, however, the output might end up > being more confusing. For example: > > The following are the 'tcpdump' options: > tcpdump version 4.99.5 > libpcap version 1.10.5 (with TPACKET_V3) > OpenSSL 3.2.4 11 Feb 2025 > 64-bit build, 64-bit time_t > Usage: tcpdump [-AbdDefhHIJKlLnNOpqStuUvxX#] [ -B size ] [ -c count ] > [--count] > [ -C file_size ] [ -E algo:secret ] [ -F file ] [ -G seconds ] > [ -i interface ] [ --immediate-mode ] [ -j tstamptype ] > [ -M secret ] [ --number ] [ --print ] [ -Q in|out|inout ] > [ -r file ] [ -s snaplen ] [ -T type ] [ --version ] > [ -V file ] [ -w file ] [ -W filecount ] [ -y datalinktype ] > [ --time-stamp-precision precision ] [ --micro ] [ --nano ] > [ -z postrotate-command ] [ -Z user ] [ expression ] > > > Here, the version info and other metadata appear before the actual > usage instructions. > Should we perhaps start dumping from “Usage” onwards? Though I’m not > sure this will work reliably for all tcpdump versions.
That doesn't seem very robust, imo. > Thoughts? I agree it can be a bit confusing, but also, right now there's confusion about what options can be passed to ovs-tcpdump and that leads people to do their own weird solutions (or even re-implement it). And though the documentation looks to be clear in most places, the missing details in '--help' creates this confusion. > //Eelco _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
