On 27 February 2012 18:38, Guy Harris <g...@alum.mit.edu> wrote: > > On Feb 27, 2012, at 9:40 AM, Nuno Martins wrote: > > > I'm having a trouble to find the purpose of pid identifier in grammar.y > > file. #line 398 > > > > This identifier is related to what protocol ? > > > > I'm supposing that this pid is not related in any way with processes > (like > > pid process identifier), right? > > Right. > > The grammar rules for pid are > > pid: nid > | qid and id > | qid or id > ; > > so it's either a nid by itself: > > nid: ID > | HID '/' NUM > | HID NETMASK HID > | HID > | HID6 '/' NUM > | HID6 > | EID > | AID > | not id > ; > > which is a "network ID" (host name, IPv4 address+netmask, IPv6 address + > CIDRish number, Ethernet ID, ATM ID, or a negated version of any of those), > or it's a qid ANDed or ORed with an id: > > qid: pnum > | pid > ; > > pnum: NUM > | paren pnum ')' > ; > > id: nid > | pnum > | paren pid ')' > ; > > The "p" in "pid" presumably refers to Parentheses, not to Protocols or > Processes; the "pid" rule exists not to define a symbol that has some > inherent semantics the user would care about, it just exists to allow the > parenthesization rules of the libpcap expression syntax to be stated.- >
Thanks, your explanation took all my doubts. Nuno Martins This is the tcpdump-workers list. > Visit https://cod.sandelman.ca/ to unsubscribe. > - This is the tcpdump-workers list. Visit https://cod.sandelman.ca/ to unsubscribe.
