
UDI IPC Methods for UNIX Hosts
5-2
Universal Debugger Interface Specification
For each connection the DFE wants to make, even if it is another connection to
the same TIP, the DFE calls
socket()
and
connect()
, creating a new socket
descriptor. All messages for that connection are then sent over that same
socket descriptor.
Note that a TIP which needs to support more than one connection will have to
listen for messages from more than one socket, and the socket that a message
arrives on implies its connection ID.
General Message Format Information
Each request or response message consists of a string of bytes. The fields of
each message are described below using the structure syntax. The fields of the
messages are always packed on byte boundaries; there are no padding bytes
between the fields.
The following field descriptors are used in the specific message formats which
start on page 5-9. The endian type of the various fields is specified on page 5-
4.
UDIUInt32
An unsigned 32–bit integer sent as 4
bytes (endian type specified on page 5-
4).
UDIInt32
A signed 32–bit integer sent as 4 bytes
(endian type specified on page 5-4).
UDIByteArray
A string of bytes. The length
or dimension of the array is always
implicit from other information and is
not sent as part of the array. (See the
dimension = comments in the specific
requests.) For the
UDIRead
,
UDIWrite
,
UDIFind
and
UDIDFEEvalExpression
requests, it is possible that the objects
specified by the byte array are not
actually bytes. In these cases, the
endian type of the objects is described
in the notes for each specific request.