T-Kernel Specification (1.B0.02)

4.2. TASK-DEPENDENT SYNCHRONIZATION FUNCTIONS 61
tk rsm tsk
tk frsm tsk
Resume Task
Force Resume Task
[C Language Interface]
ER ercd = tk_rsm_tsk ( ID tskid ) ;
ER ercd = tk_frsm_tsk ( ID tskid ) ;
[Parameters]
ID tskid Task ID
[Return Parameters]
ER ercd Error code
[Error Codes]
E OK
E ID
E NOEXS
E OBJ
Normal completion
Invalid ID number (tskid is invalid or cannot be used)
Object does not exist (the task designated in tskid does not exist)
Invalid object state (the designated task is not in SUSPEND state (including when this
system call designates the invoking task or a task in DORMANT state))
[Description]
Releases the SUSPEND state of the task designated in tskid.
If the target task was earlier put in SUSPEND state by the tk sus tsk system call, this system call
releases that SUSPEND state and resumes the task execution.
When the target task is in a combined WAIT state and SUSPEND state (WAIT-SUSPEND state),
executing tk rsm tsk releases only the SUSPEND state, putting the task in WAIT state.
This system call cannot be issued for the invoking task. If the invoking task is designated, error code
E OBJ is returned.
Executing tk rsm tsk one time clears only one nested suspend request (suscnt). If tk sus tsk was
issued more than once for the target task (suscnt ≥ 2), the target task remains in SUSPEND state
even after tk rsm tsk is executed. When tk frsm tsk is issued, on the other hand, all suspend requests
are released (suscnt is cleared to 0) even if tk sus tsk was issued more than once (suscnt ≥ 2). The
SUSPEND state is always cleared, and unless the task was in WAIT-SUSPEND state its execution
resumes.
[Additional Notes]
After a task in RUN state or READY state is put in SUSPEND state by tk sus tsk and then resumed
by tk rsm tsk or tk frsm tsk, the task has the lowest precedence among tasks of the same priority.
Copyright c○ 2002, 2003 by T-Engine Forum
T-Kernel 1.B0.02