DB2 Version 9.7 for Linux, UNIX, and Windows

REMOVE_PIPE function - Delete a pipe

The REMOVE_PIPE function deletes an explicitly created pipe. Use this function to delete any public or private pipe that was created by the CREATE_PIPE function.

Syntax


>>-DBMS_PIPE.REMOVE_PIPE--(--pipename -)-----------------------><

Return value

This function returns one of the following status codes of type INTEGER.

Table 1. REMOVE_PIPE status codes
Status code	Description
0	Pipe successfully removed or does not exist
NULL	An exception is thrown

Function parameters

pipename: An input argument of type VARCHAR(128) that specifies the name of the pipe.

Authorization

EXECUTE privilege on the DBMS_PIPE module.

Example

In proc1 send two messages on a pipe: Message #1 and Message #2. In proc2, receive the first message, unpack it, and then delete the pipe. When proc3 runs, the call to the RECEIVE_MESSAGE function times out and returns the status code 1 because the pipe no longer exists.

SET SERVEROUTPUT ON@ 

CREATE PROCEDURE proc1()
BEGIN
  DECLARE    v_status        INTEGER;
  DECLARE    status          INTEGER;
  SET  v_status = DBMS_PIPE.CREATE_PIPE('pipe1');
  CALL DBMS_OUTPUT.PUT_LINE('CREATE_PIPE status : ' || v_status);

  SET status = DBMS_PIPE.PACK_MESSAGE('Message #1');
  SET v_status = DBMS_PIPE.SEND_MESSAGE('pipe1');
  CALL DBMS_OUTPUT.PUT_LINE('SEND_MESSAGE status: ' || v_status);

  SET status = DBMS_PIPE.PACK_MESSAGE('Message #2');
  SET v_status = DBMS_PIPE.SEND_MESSAGE('pipe1');
  CALL DBMS_OUTPUT.PUT_LINE('SEND_MESSAGE status: ' || v_status);
END@

CREATE PROCEDURE proc2()
BEGIN
  DECLARE    v_item          VARCHAR(80);
  DECLARE    v_status        INTEGER;
  DECLARE    status          INTEGER;
  SET v_status = DBMS_PIPE.RECEIVE_MESSAGE('pipe1',1);
  CALL DBMS_OUTPUT.PUT_LINE('RECEIVE_MESSAGE status: ' || v_status);
  CALL DBMS_PIPE.UNPACK_MESSAGE(v_item);
  CALL DBMS_OUTPUT.PUT_LINE('Item: ' || v_item);
  SET status = DBMS_PIPE.REMOVE_PIPE('pipe1');
END@

CREATE PROCEDURE proc3()
BEGIN
  DECLARE    v_item          VARCHAR(80);
  DECLARE    v_status        INTEGER;
  SET v_status = DBMS_PIPE.RECEIVE_MESSAGE('pipe1',1);
  CALL DBMS_OUTPUT.PUT_LINE('RECEIVE_MESSAGE status: ' || v_status);
END@

CALL proc1@

CALL proc2@

CALL proc3@

This example results in the following output.

From proc1:

CREATE_PIPE status : 0
SEND_MESSAGE status: 0
SEND_MESSAGE status: 0

From proc2:

RECEIVE_MESSAGE status: 0
Item: Message #1

From proc3:

RECEIVE_MESSAGE status: 1