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<chapter id="libpq">

<title><application>libpq</application> - C Library</title>

system's documentation for information about how to build

thread-enabled applications, or look in

<filename>src/Makefile.global</filename> for <literal>PTHREAD_CFLAGS</>

and <literal>PTHREAD_LIBS</>.

and <literal>PTHREAD_LIBS</>. This function allows the querying of

<application>libpq</application>'s thread-safe status:

</para>

<variablelist>

<varlistentry>

<term><function>PQisthreadsafe</function><indexterm><primary>PQisthreadsafe</></></term>

<listitem>

<para>

Returns the thread safety status of the <application>libpq</application>

library.

<synopsis>

int PQisthreadsafe();

</synopsis>

</para>

<para>

Returns 1 if the <application>libpq</application> is thead-safe and

0 if it is not.

</para>

</listitem>

</varlistentry>

</variablelist>

<para>

One restriction is that no two threads attempt to manipulate the same

Onethreadrestriction is that no two threads attempt to manipulate the same

<structname>PGconn</> object at the same time. In particular, you cannot

issue concurrent commands from different threads through the same

connection object. (If you need to run concurrent commands, use

# $PostgreSQL: pgsql/src/interfaces/libpq/exports.txt,v 1.8 2006/05/21 20:19:23 tgl Exp $

# $PostgreSQL: pgsql/src/interfaces/libpq/exports.txt,v 1.9 2006/05/23 22:13:19 momjian Exp $

# Functions to be exported by libpq DLLs

PQconnectdb 1

PQsetdbLogin 2

PQescapeStringConn 126

PQescapeByteaConn 127

PQencryptPassword 128

PQisthreadsafe 129

returnpqIsnonblocking(conn);

}

PQisthreadsafe(void)

{

return true;

return false;

}

PQflush(PGconn*conn)

externintPQsetnonblocking(PGconn*conn,intarg);

externintPQisnonblocking(constPGconn*conn);

externintPQisthreadsafe(void);

externintPQflush(PGconn*conn);