Specify buffers

The queue manager refers to buffers only if they are required. If you do not require a buffer on a call or the buffer is zero in length, we can use a null pointer to a buffer.

Always use datalength when specifying the size of the buffer that you require.

When we use a buffer to hold the output from a call (for example, to hold the message data for an MQGET call, or the values of attributes queried by the MQINQ call), the queue manager attempts to return a reason code if the buffer you specify is not valid or is in read-only storage. However, it might not always be able to return a reason code.

Parent topic: The Message Queue Interface overview