T-Kernel Specification (1.B0.02)

4.6. MEMORY POOL MANAGEMENT FUNCTIONS 161
tk rel mpl
Release Variable-size Memory Block
[C Language Interface]
ER ercd = tk_rel_mpl ( ID mplid, VP blk ) ;
[Parameters]
ID mplid Variable-size memory pool ID
VP blf Memory block start address
[Return Parameters]
ER ercd Error code
[Error Codes]
E OK
E ID
E NOEXS
E PAR
Normal completion
Invalid ID number (mplid is invalid or cannot be used)
Object does not exist (the variable-size memory pool designated in mplid does not exist)
Parameter error (blk is invalid, or block returned to wrong memory pool)
[Description]
Returns the memory block designated in blk to the variable-size memory pool designated in mplid.
Executing tk rel mpl may enable memory block acquisition by another task waiting to allocate memory
from the memory pool designated in mplid, releasing the WAIT state of that task.
When a memory block is returned to a variable-size memory pool, it must be the same variable-size
memory pool from which the block was allocated. If an attempt to return a memory block to a different
memory pool is detected, error code E PAR is returned. Whether this error detection is made or not is
implementation-dependent.
[Additional Notes]
When memory is returned to a variable-size memory pool in which multiple tasks are queued, multiple
tasks may be released at the same time depending on the amount of memory returned and their requested
memory size. The task precedence among tasks of the same priority after their WAIT state is released
in such a case is the order in which they were queued.
Copyright c○ 2002, 2003 by T-Engine Forum
T-Kernel 1.B0.02