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-rw-r--r--src/test/examples/testlibpq2.c93
1 files changed, 93 insertions, 0 deletions
diff --git a/src/test/examples/testlibpq2.c b/src/test/examples/testlibpq2.c
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+++ b/src/test/examples/testlibpq2.c
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+/*
+ * testlibpq2.c
+ * Test of the asynchronous notification interface
+ *
+ populate a database with the following:
+
+CREATE TABLE TBL1 (i int4);
+
+CREATE TABLE TBL2 (i int4);
+
+CREATE RULE r1 AS ON INSERT TO TBL1 DO [INSERT INTO TBL2 values (new.i); NOTIFY TBL2];
+
+ * Then start up this program
+ * After the program has begun, do
+
+INSERT INTO TBL1 values (10);
+
+ *
+ *
+ */
+#include <stdio.h>
+#include "libpq-fe.h"
+
+void exit_nicely(PGconn* conn)
+{
+ PQfinish(conn);
+ exit(1);
+}
+
+main()
+{
+ char *pghost, *pgport, *pgoptions, *pgtty;
+ char* dbName;
+ int nFields;
+ int i,j;
+
+ PGconn* conn;
+ PGresult* res;
+ PGnotify* notify;
+
+ /* begin, by setting the parameters for a backend connection
+ if the parameters are null, then the system will try to use
+ reasonable defaults by looking up environment variables
+ or, failing that, using hardwired constants */
+ pghost = NULL; /* host name of the backend server */
+ pgport = NULL; /* port of the backend server */
+ pgoptions = NULL; /* special options to start up the backend server */
+ pgtty = NULL; /* debugging tty for the backend server */
+ dbName = getenv("USER"); /* change this to the name of your test database*/
+
+ /* make a connection to the database */
+ conn = PQsetdb(pghost, pgport, pgoptions, pgtty, dbName);
+
+ /* check to see that the backend connection was successfully made */
+ if (PQstatus(conn) == CONNECTION_BAD) {
+ fprintf(stderr,"Connection to database '%s' failed.\n", dbName);
+ fprintf(stderr,"%s",PQerrorMessage(conn));
+ exit_nicely(conn);
+ }
+
+ res = PQexec(conn, "LISTEN TBL2");
+ if (PQresultStatus(res) != PGRES_COMMAND_OK) {
+ fprintf(stderr,"LISTEN command failed\n");
+ PQclear(res);
+ exit_nicely(conn);
+ }
+ /* should PQclear PGresult whenever it is no longer needed to avoid
+ memory leaks */
+ PQclear(res);
+
+ while (1) {
+ /* async notification only come back as a result of a query*/
+ /* we can send empty queries */
+ res = PQexec(conn, " ");
+/* printf("res->status = %s\n", pgresStatus[PQresultStatus(res)]); */
+ /* check for asynchronous returns */
+ notify = PQnotifies(conn);
+ if (notify) {
+ fprintf(stderr,
+ "ASYNC NOTIFY of '%s' from backend pid '%d' received\n",
+ notify->relname, notify->be_pid);
+ free(notify);
+ break;
+ }
+ PQclear(res);
+ }
+
+ /* close the connection to the database and cleanup */
+ PQfinish(conn);
+
+}
+
+