In PQnotifies discussion, reference PQsocket as function needed to get

file descriptor number for select().  (Suggestion from Ken Wright.)

diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml
index b700ce44975754d5f83c628f8cde9939c0d571ba..c8cc2ee3e660518809d0677486ba324a86aee79d 100644 (file)
--- a/doc/src/sgml/libpq.sgml
+++ b/doc/src/sgml/libpq.sgml
@@ -1460,13 +1460,17 @@ deprecated as a waste of processing power.
 
 A better way to check for NOTIFY
 messages when you have no useful queries to make is to call
-PQconsumeInput(), then check PQnotifies().
+PQconsumeInput(), then check
+PQnotifies().
 You can use select(2) to wait for backend data to
 arrive, thereby using no CPU power unless there is something
-to do.  Note that this will work OK whether you use PQsendQuery/
-PQgetResult or simply PQexec for
-queries.  You should, however, remember to check PQnotifies()
-after each PQgetResult or PQexec to see
+to do.  (See PQsocket() to obtain the file descriptor
+number to use with select.)
+Note that this will work OK whether you submit queries with
+PQsendQuery/PQgetResult or simply
+use PQexec.  You should, however, remember to
+check PQnotifies() after each
+PQgetResult or PQexec, to see
 if any notifications came in during the processing of the query.