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linux环境支持psos的操作系统。非常适合进行移植的朋友。

/*****************************************************************************
 * README - Please read this file first to get more information about 
 *          the pSos+ to Linux library--p2linux.a.
 ****************************************************************************/

1  Although some key APIs of pSOS+ have been implemented, support of these features requires
   an 'adpter layer' of code which adds functionality at the inevitable expense of raw 
   performance.

2  This library only support one node architecture, it is mean that you can only using it in 
   one processor board, and set the arg of "node" to zero in APIs;

3  When you create the task with t_create API, you'd better limit your priority of task in 
   1--98, any other value will also be translated to this in this area by the function.

4  The 'event' mechanism has been implemented, but it designed only for signal tansport inter 
   user-space, so the safe when using it between kernel-space and user-space should not be 
   guaranteed.

5  Under VxWorks enviroment, pt_create function require the user to specify the 'paddr' arg, 
   that is because in such a real-time OS, it's left user to manage the memory by himself, but
   here you have to be gaurantee that the "paddr" must has not been used, maybe 'malloc' before 
   the call is a good choice.

6  We didn't use the System V message queue and semaphore support for it's complexity, and 
   implement it by ourselves, so it can be used to vary linux version.

7  Function q_broadcast() gives a copy of the input message to each such task and makes it 
   ready to run. After a q_broadcast() call, no tasks will be waiting to receive a message 
   from the specified queue, and this is the same as the pSOS+ q_broadcast() system call.

8  In some functions like my_tcb() which are not exposed outside as APIs, since the access 
   is read-only, no locking of the task list is done there.

9  If the user want to malloc a memory, you'd better using the thread-safe malloc 'ts_malloc()'
   Provided by this library, so does the 'ts_free()' function.

10 In fuction t_start(), only the mode T_TSLICE,T_NOTSLICE is supported, and the flags T_PREEMPT
   and T_NOPREEMPT is useless here since the priority of the task has been set by the arg 'prio'
   of t_create() function. Also In function t_mode, only the mode T_TSLICE | T_NOTSLICE |
   T_PREEMPT | T_NOPREEMPT has been supported.

11 In t_suspend() function, if the task has been locked(the highest priority), i do nothing.

12 In Linux enviroment, the default ticks per second is 100.