I propose to settle this issue by applying "Robert's changes two and three", which has been +1'd by two people already and I also accept myself as improvement. I don't think any further changes are required.
diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml index c1d1b6b2db..7afe7bf68d 100644 --- a/doc/src/sgml/libpq.sgml +++ b/doc/src/sgml/libpq.sgml @@ -993,10 +993,14 @@ postgresql://%2Fvar%2Flib%2Fpostgresql/dbname your machine supports IPv6, you can also use those addresses. TCP/IP communication is always used when a nonempty string is specified for this parameter. + If this parameter is not specified, the value of <literal>host</literal> + will be looked up to find the corresponding IP address - or, if + <literal>host</literal> specifies an IP address, that value will be + used directly. </para> <para> - Using <literal>hostaddr</literal> instead of <literal>host</literal> allows the + Using <literal>hostaddr</literal> allows the application to avoid a host name look-up, which might be important in applications with time constraints. However, a host name is required for GSSAPI or SSPI authentication In absence of objections or better ideas, I'll get this pushed tomorrow. If Robert as patch author wants to push himself, I'm happy to stand aside. -- Álvaro Herrera https://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services