NTXHANDLE ntxCreateRtMailbox( 
    NTXLOCATION hLocation, 
    DWORD dwFlags 
);

hLocation

The location handle of the Client Node on which the mailbox will be created.

dwFlags

Specifies flags that control creation of the mailbox. Possible values are described below. Values may be combined where appropriate.

NTX_OBJECT_MAILBOX	This flag indicates that the mailbox is to be created to pass RT object handles. It is mutually exclusive with the NTX_DATA_MAILBOX flag. The depth of the mailbox may be specified by the MAILBOX_DEPTH(n) macro.
NTX_DATA_MAILBOX	This flag indicates that the mailbox is to be created to pass up to 128-byte messages. In this case the depth of the mailbox is initially 3 messages.
NTX_FIFO_QUEUING	This flag indicates that threads will be queued in First-In-First-Out order on this object.
NTX_PRIORITY_QUEUING	This flag indicates that threads will be queued in priority order on this object.
MAILBOX_DEPTH(n)	This macro determines the number of objects which can be queued in an object mailbox. It is ignored for data mailboxes. The value n must be at least 8, at most 64, and a multiple of 4.