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<chapter id="libpq">

<listitem>

<para>

IP address of host to connect to. This should be in standard

numbers-and-dots form, as used by the BSD functions <function>inet_aton</> et al. If

a nonzero-length string is specified, TCP/IP communication is used.

IPv4 address format, e.g. <literal>172.28.40.9</>. If your machine

supports IPv6, you can also use those addresses. If a nonzero-length

string is specified, TCP/IP communication is used.

</para>

<para>

Using <literal>hostaddr</> instead of host allows the application to avoid a host

name look-up, which may be important in applications with time

constraints. However, Kerberos authentication requires the host

name. The following therefore applies. If host is specified without

name. The following therefore applies: If host is specified without

<literal>hostaddr</>, a host name lookup is forced. If <literal>hostaddr</> is specified without

host, the value for <literal>hostaddr</> gives the remote address; if Kerberos is

used, this causes a reverse name query. If both host and <literal>hostaddr</> are

"Database-Host","",40},

{"hostaddr","PGHOSTADDR",NULL,NULL,

"Database-Host-IPv4-Address","",15},/* Room for

"Database-Host-IP-Address","",45},

{"port","PGPORT",DEF_PGPORT_STR,NULL,

"Database-Port","",6},