From: | Kynn Jones <kynnjo(at)gmail(dot)com> |
---|---|
To: | pgsql-general General <pgsql-general(at)postgresql(dot)org> |
Subject: | Re: Which header and lib files to use when compiling libpq-code? |
Date: | 2009-04-27 16:27:37 |
Message-ID: | c2350ba40904270927x71c741edq7a96da2c6638ca9d@mail.gmail.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-general |
On Mon, Apr 27, 2009 at 11:10 AM, Martijn van Oosterhout
<kleptog(at)svana(dot)org>wrote:
> On Mon, Apr 27, 2009 at 10:51:45AM -0400, Kynn Jones wrote:
> > I need to compile some code that uses libpq. For this I need to
> determine
> > the directories to use for the header and library files.
> >
> > The machine I'm using has multiple copies of the files libpq-fe.h and
> > libpq.a. How can I determine which one of all these copies are the ones
> > that correspond to the Pg server that is currently running on this
> system?
> > (FWIW, the OS here is Ubuntu Linux.)
>
> In general you don't need to match the server version, the protocol
hasn't changed much in a while so as long as it's less than a few years
> old it'll work.
This statement contradicts the experience I described in my original post:
the choice of header and/or library files is absolutely critical. The wrong
choice lead to very bizarre connection failures.
> > I tried the naive approach of using the "newest" versions of these files,
> as
> > measured by their modification times. This produced disastrous results.
> > The code compiled, but resulted in a program that failed in bizarre and
> > unpredictable ways, which strongly hinted at one or more silent
> segmentation
> > violations in the C code. I conjectured that this was the result of a
> > mismatched header or library file. Sure enough, the bizarre failures
> > disappeared when I used a different set of header and library files.
>
> Given you're using Ubuntu, why not just install postgresql-dev and use
> /usr/include/postgresql.
>
I don't have root privileges on this machine, so I could not install
postgresql-dev, but, as it happens, /usr/include/postgresql already exists
in this machine, in it is, in fact, the version that worked.
But this is not the problem that my question was about. The problem is:
*how to ensure* that the versions of libpq header and library files used for
compiling programs will work properly with a specific Postgres server.
kynn
From | Date | Subject | |
---|---|---|---|
Next Message | Tom Lane | 2009-04-27 16:29:41 | Re: find column OID types with information schema? |
Previous Message | Tom Lane | 2009-04-27 16:23:44 | Re: how do you get there from here? |