Hi, I use FreeBSD 10.0-BETA3 amd64, upgraded from 9.2-RELEASE with freebsd-update. I was capturing with tcpdump and doing some grep on it: # tcpdump -li nfe0 port 53 | grep Refused > capture.txt I was surprised that capture.txt is totally empty. If I don't redirect the output, then it writes what I need on stdout. It's very very strange? -- Florent Peterschmitt | Please: florent at peterschmitt.fr | * Avoid HTML/RTF in E-mail. +33 (0)6 64 33 97 92 | * Send PDF for documents. http://florent.peterschmitt.fr | * Trim your quotations. Really. Proudly powered by Open Source | Thank you :) -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 901 bytes Desc: OpenPGP digital signature URL: <http://lists.freebsd.org/pipermail/freebsd-stable/attachments/20131120/91c15fc6/attachment.sig>
On 20 Nov 2013, at 19:44, Florent Peterschmitt <florent at peterschmitt.fr> wrote:> I use FreeBSD 10.0-BETA3 amd64, upgraded from 9.2-RELEASE with > freebsd-update. > > I was capturing with tcpdump and doing some grep on it: > > # tcpdump -li nfe0 port 53 | grep Refused > capture.txt > > I was surprised that capture.txt is totally empty. If I don't redirect > the output, then it writes what I need on stdout.Try grep --line-buffered instead (which incurs a performance penalty, but you probably don't care in this case). BSD grep also supports this option. -Dimitry -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 203 bytes Desc: Message signed with OpenPGP using GPGMail URL: <http://lists.freebsd.org/pipermail/freebsd-stable/attachments/20131120/dd8fc0ea/attachment.sig>