Обсуждение: Wire protocol docs
On http://www.postgresql.org/docs/8.4/interactive/protocol.html we say: "Higher level features built on this protocol (for example, how libpq passes certain environment variables when the connection is established) are covered elsewhere." I cannot find anything that is obviously 'elsewhere' in the docs - does that need fixing, or do my searching skills need improving? *starts reading source code* :-) -- Dave Page EnterpriseDB UK: http://www.enterprisedb.com
At 2009-10-13 17:25:15 +0100, dpage@pgadmin.org wrote: > > I cannot find anything that is obviously 'elsewhere' in the docs - > does that need fixing, or do my searching skills need improving? I don't know, but… > *starts reading source code* :-) Look at what fe-protocol3.c:build_startup_packet() does with its options argument (and see fe-connect.c:EnvironmentOptions to see what is passed to it). Basically, libpq sets some connection parameters to values taken from the environment (e.g. client_encoding from PGCLIENTENCODING). What the documentation you quoted is saying is that the wire protocol doesn't know or care where the values came from. -- ams
On Tue, Oct 13, 2009 at 5:41 PM, Abhijit Menon-Sen <ams@toroid.org> wrote: > At 2009-10-13 17:25:15 +0100, dpage@pgadmin.org wrote: >> >> I cannot find anything that is obviously 'elsewhere' in the docs - >> does that need fixing, or do my searching skills need improving? > > I don't know, but… > >> *starts reading source code* :-) > > Look at what fe-protocol3.c:build_startup_packet() does with its options > argument (and see fe-connect.c:EnvironmentOptions to see what is passed > to it). Basically, libpq sets some connection parameters to values taken > from the environment (e.g. client_encoding from PGCLIENTENCODING). Yeah, grep found that pretty quickly :-) > What > the documentation you quoted is saying is that the wire protocol doesn't > know or care where the values came from. Right. My complaint though, is that the docs imply that the info on how those values get set is in the docs somewhere, which appears to be incorrect. -- Dave Page EnterpriseDB UK: http://www.enterprisedb.com
On Tue, 13 Oct 2009, Dave Page wrote: > On http://www.postgresql.org/docs/8.4/interactive/protocol.html we say: > > "Higher level features built on this protocol (for example, how libpq > passes certain environment variables when the connection is > established) are covered elsewhere." http://www.postgresql.org/docs/8.4/static/libpq-envars.html and http://www.postgresql.org/docs/8.4/static/libpq-connect.html are what I think it's alluding to here. -- * Greg Smith gsmith@gregsmith.com http://www.gregsmith.com Baltimore, MD
Dave Page <dpage@pgadmin.org> writes:
> Right. My complaint though, is that the docs imply that the info on
> how those values get set is in the docs somewhere, which appears to be
> incorrect.
The libpq documentation does cover the fact that libpq uses those
variables to establish initial settings. I wouldn't expect it to
go into implementation details, would you?
regards, tom lane
On Tue, Oct 13, 2009 at 6:24 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote: > Dave Page <dpage@pgadmin.org> writes: >> Right. My complaint though, is that the docs imply that the info on >> how those values get set is in the docs somewhere, which appears to be >> incorrect. > > The libpq documentation does cover the fact that libpq uses those > variables to establish initial settings. I wouldn't expect it to > go into implementation details, would you? Not the libpq docs, no. I was expecting something to though, having been told in the intro to the low level protocol details that: "Higher level features built on this protocol (for example, how libpq passes certain environment variables when the connection is established) are covered elsewhere." Note that it says *how* libpq passes those variables which implies the mechanism of passing them to the server. Anyway, I can figure out what I need from the existing code - I just found that sentence misleading and think it should probably be removed. -- Dave Page EnterpriseDB UK: http://www.enterprisedb.com
Dave Page wrote: > On Tue, Oct 13, 2009 at 6:24 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote: > > Dave Page <dpage@pgadmin.org> writes: > >> Right. My complaint though, is that the docs imply that the info on > >> how those values get set is in the docs somewhere, which appears to be > >> incorrect. > > > > The libpq documentation does cover the fact that libpq uses those > > variables to establish initial settings. ?I wouldn't expect it to > > go into implementation details, would you? > > Not the libpq docs, no. I was expecting something to though, having > been told in the intro to the low level protocol details that: > > "Higher level features built on this protocol (for example, how libpq > passes certain environment variables when the connection is > established) are covered elsewhere." > > Note that it says *how* libpq passes those variables which implies the > mechanism of passing them to the server. Anyway, I can figure out what > I need from the existing code - I just found that sentence misleading > and think it should probably be removed. Agreed, removed. -- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB http://enterprisedb.comPG East: http://www.enterprisedb.com/community/nav-pg-east-2010.do + If your life is a hard drive,Christ can be your backup. +