This chapter gives detailed explanations of the functions provided by T-Kernel Debugger Support (T-Kernel/DS).
T-Kernel/DS provides functions enabling a debugger to reference T-Kernel internal states and run a trace. The functions provided by T-Kernel/DS are only for debugger use and not for use by applications or other programs.
- Except where otherwise noted, T-kernel/DS service calls (td_) can be called from a task independent portion and while dispatching and interrupts are disabled. There may be some limitations, however, imposed by particular implementations.
- When T-Kernel/DS service calls (td_) are invoked in interrupts disabled state, they are processed without enabling interrupts. Other OS states likewise remain unchanged during this processing. Changes in OS states may occur if a service call is invoked while interrupts or dispatching are enabled, since the OS continues operating.
- T-Kernel/DS service calls (td_) cannot be invoked from a lower protection level than that at which T-Kernel/OS system calls can be invoked (lower than TSVCLimit)(
- Error codes such as
E_CTXthat always have the possibility of occurring are not described here unless there is some special reason for doing so.
- Detection of error codes
E_CTXis implementation-dependent; these may not always be detected as error. For this reason, the service calls must not be invoked in such a way that these errors might occur.