T-Kernel Specification (1.B0.02)

98 CHAPTER 4. T-KERNEL/OS FUNCTIONS
tk cre mbx
Create Mailbox
[C Language Interface]
ID mbxid = tk_cre_mbx ( T_CMBX* pk_cmbx ) ;
[Parameters]
T CMBX* pk cmbx Information about the mailbox to be created
pk cmbx detail:
VP exinf Extended information
ATR mbxatr Mailbox attributes
(Other implementation-dependent parameters may be added beyond this point.)
[Return Parameters]
ID mbxid Mailbox ID
or Error Code
[Error Codes]
E OK
E NOMEM
E LIMIT
E RSATR
E PAR
Normal completion
Insufficient memory (memory for a control block or buffer cannot be allocated)
Number of mailboxes exceeds the system limit
Reserved attribute (mbxatr is invalid or cannot be used)
Parameter error (pk cmbx is invalid)
[Description]
Creates a mailbox, assigning to it a mailbox ID.
This system call allocates a control block, etc. for the created mailbox.
exinf can be used freely by the user to set miscellaneous information about the created mailbox. The
information set in this parameter can be referenced by tk ref mbx. If a larger area is needed for
indicating user information, or if the information may need to be changed after the mailbox is created,
this can be done by allocating separate memory for this purpose and putting the memory packet address
in exinf. The OS pays no attention to the contents of exinf.
mbxatr indicates system attributes in its low bits and implementation-dependent information in the
high bits. Designation in the system attributes part of mbxatr is as follows.
mbxatr:= (TA_TFIFO || TA_TPRI) | (TA_MFIFO || TA_MPRI) | [TA\_NODISWAI]
Copyright c○ 2002, 2003 by T-Engine Forum
T-Kernel 1.B0.02