server host, not the local host!

</para>

</listitem>

<listitem>

<para>

<function>PQsetenvStart</function>

<function>PQsetenvPoll</function>

<function>PQsetenvAbort</function>

Perform an environment negotiation.

<synopsis>

PGsetenvHandle *PQsetenvStart(PGconn *conn)

</synopsis>

<synopsis>

PostgresPollingStatusType *PQsetenvPoll(PGsetenvHandle handle)

</synopsis>

<synopsis>

void PQsetenvAbort(PGsetenvHandle handle)

</synopsis>

These two routines can be used to re-perform the environment negotiation

that occurs during the opening of a connection to a database

server. I have

no idea why this might be useful (XXX anyone?) but it might prove useful

for users to be able to reconfigure their character encodings

on-the-fly, for example.

</para>

<para>

These functions will not block, subject to the restrictions applied to

PQconnectStart and PQconnectPoll.

</para>

<para>

To begin, call handle=PQsetenvStart(conn), where conn is an open connection

to the database server. If handle is NULL, then libpq has been unable to

allocate a new PGsetenvHandle structure. Otherwise, a valid handle is

returned. This handle is intended to be opaque - you may only use it to

call other functions in libpq (PQsetenvPoll, for example).

</para>

<para>

Poll the procedure using PQsetenvPoll, in exactly the same way as you would

create a connection using PQconnectPoll.

</para>

<para>

The procedure may be aborted at any time by calling PQsetenvAbort(handle).

</para>

</listitem>

<listitem>

<para>

<function>PQsetenv</function>

Perform an environment negotiation.

<synopsis>

int PQsetenv(PGconn *conn)

</synopsis>

This function performs the same duties as PQsetenvStart and

PQsetenvPoll, but

blocks to do so. It returns 1 on success and 0 on failure.

</para>

</listitem>

</itemizedlist>

</para>

</sect1>