
UDI Services
Universal Debugger Interface Specification
3-15
The way the
Configuration
parameter is translated for DOS hosts and for
UNIX hosts is described in detail in Appendix B. In general, IPC layers use a
configuration file where each line contains the configuration name, the TIP
program name, and other TIP–specific options. For example, a simulator TIP
might have several lines in the file where each line represents different
configurations of the simulator that the user has set up and named.
Session
points to an object that will be used to identify this DFE–TIP
connection in future session management UDI calls.
After a successful
UDIConnect
, the current connection is the one just
connected and the current process for that connection is
UDIProcessProcessor
. If an error is returned, the connection was not
established. If the error is negative, the DFE can call
UDIGetErrorMsg
and
must call
UDIDisconnect
. No other service requests are permitted if an error is
returned.
To solve certain problems, the IPC Layer (prior to spawning a new TIP and
calling the new TIP’s
UDIConnect
function) can call
UDIConnect
at each
currently running TIP that has the same executable file name as the desired
configuration. Because TIPs may need exclusive access to either TIP or target
resources, TIPs may need to either prevent or force the IPC Layer to spawn a
new TIP.
One such example is a TIP that communicates with a private target. The TIP
should ensure that no other TIPs are spawned that might contend for the same
target. Such TIPs, when called at
UDIConnect
for a configuration that would
create the contention, should return
UDIErrorConnectionUnavailable
. The
IPC Layer will recognize this error and return to the DFE immediately, rather
than attempting to find or spawn another TIP to satisfy the request.
In another example, a TIP that can support multiple connections by spawning
multiple TIPs, like a simulator, needs to return only
UDIErrorTryAnotherTIP
. This causes the IPC Layer to check other installed
TIPs and, if necessary, attempt to spawn another instance of the same TIP.