On 18/02/2023 21:51, Denis Ovsienko wrote: > On Sat, 18 Feb 2023 17:06:29 +0100 > Francois-Xavier Le Bail <devel.fx.leb...@orange.fr> wrote: > >> Hello, >> >> https://www.rfc-editor.org/rfc/rfc9293 states: >> "Control bits: >> >> The control bits are also known as "flags". Assignment is managed >> by IANA from the "TCP Header Flags" registry [62]. The currently >> assigned control bits are CWR, ECE, URG, ACK, PSH, RST, SYN, and FIN." >> >> (All on three characters.) >> >> To be in sync with it, we could use 'tcp-psh' in addition to >> 'tcp-push' in libpcap scanner.l, and in pcap-filter.7 and tcpdump.1 >> man pages. > > That's an interesting point. Adding "tcp-psh" would certainly restore > consistency with the registry on one hand. On the other, for backward > compatibility reasons "tcp-push" would have to remain a valid alias for > who knows how many years.
We could keep "tcp-push" indefinitely... > I wonder if there would be any other incurred future maintenance. > > The fact tcpdump(1) prose says "PUSH" instead of "PSH" may be related > to the origin of this discrepancy. Perhaps this is the only part that > can be fixed immediately without unwanted side effects. There is not even consistency in the tcpdump man page (PUSH and PSH): $ git grep -En '\<(PSH|PUSH)\>' tcpdump.1.in tcpdump.1.in:1322:F (FIN), P (PUSH), R (RST), U (URG), W (ECN CWR), E (ECN-Echo) or tcpdump.1.in:1389:The PUSH flag is set in the packet. tcpdump.1.in:1415:.I CWR | ECE | URG | ACK | PSH | RST | SYN | FIN tcpdump.1.in:1486:left, so the PSH bit is bit number 3, while the URG bit is number 5. _______________________________________________ tcpdump-workers mailing list -- tcpdump-workers@lists.tcpdump.org To unsubscribe send an email to tcpdump-workers-le...@lists.tcpdump.org %(web_page_url)slistinfo%(cgiext)s/%(_internal_name)s
