Initial revision

1 files changed, 74 insertions, 0 deletions

diff --git a/lisp/test/psql-2.lsp b/lisp/test/psql-2.lsp
new file mode 100644
index 0000000..011512c
--- /dev/null
+++ b/lisp/test/psql-2.lsp
@@ -0,0 +1,74 @@
+;; Postgresql C library interface, example program 2, using the xedit
+;; lisp interface
+
+;;  Test of the asynchronous notification interface
+;;
+;; Start this program, then from psql in another window do
+;;   NOTIFY TBL2;
+;;
+;; Or, if you want to get fancy, try this:
+;; 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);
+;;
+;; and do
+;;
+;;   INSERT INTO TBL1 values (10);
+(require "psql")
+
+(defun exit-nicely (conn)
+    (pq-finish conn)
+    (quit 1)
+)
+
+;; 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
+(setq pghost nil)		; host name of the backend server
+(setq pgport nil)		; port of the backend server
+(setq pgoptions nil)		; special options to start up the backend server
+(setq pgtty nil)		; debugging tty for the backend server
+(setq pgdbname "test")		; change this to the name of your test database
+				;; XXX Note: getenv not yet implemented in the
+				 ; lisp interpreter
+
+;; make a connection to the database
+(setq conn (pq-setdb pghost pgport pgoptions pgtty pgdbname))
+
+;; check to see that the backend connection was successfully made
+(when (= (pq-status conn) pg-connection-bad)
+    (format t "Connection to database '~A' failed.~%" pgdbname)
+    (format t "~A" (pq-error-message conn))
+    (exit-nicely conn))
+
+(setq res (pq-exec conn "LISTEN TBL2"))
+(when (= (pq-status conn) pg-connection-bad)
+    (format t "LISTEN command failed~%")
+    (format t "~A" (pq-error-message conn))
+    (exit-nicely conn))
+
+;; Should PQclear PGresult whenever it is no longer needed to avoid memory leaks
+(pq-clear res)
+
+(loop
+    ;; wait a little bit between checks; waiting with select()
+    ;; would be more efficient.
+	;; XXX Note: sleep not yet implemented in the lisp interpreter
+
+    ;; collect any asynchronous backend messages
+    (pq-consume-input conn)
+
+    ;; check for asynchronous notify messages
+    (when (setq notifies (pq-notifies conn))
+	(format t "ASYNC NOTIFY of '~A' from backend pid '~D' received~%"
+	 (pg-notify-relname notifies) (pg-notify-be-pid notifies))
+    )
+)
+
+(pq-finish conn)