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Altera_Forum
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16 years ago

NicheStack multiple select() call fails!

Hello @ all, I have created two (or more) networktasks in the µC/OS-II enviroment wich are using the Niche TCP/IP Stack. When i perform a select() call from both tasks to there sockets, only the s...
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Altera_Forum
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16 years ago

G'day BWEIBERG,

I'll need to have a closer look at your changes.

One change that I've made is to the following lines: 

    
   if ((tcb = (OS_TCB *)OSTCBPrioTbl) == (OS_TCB *)NULL) 
      continue; //unassigned priority

changed to: 

    
      tcb = (OS_TCB *)OSTCBPrioTbl;
      if ( (tcb == (OS_TCB *)NULL) || (tcb == OS_TCB_RESERVED ) )
         continue;    /* unassigned priority */

Ucos flags a priority as reserved when using mutexes, so just checking for NULL is not sufficent. You'll get an access violation or misaligned address exception if you don't make this change. (or other weird behavior if you don't have the MPU / MMU on)

I'm pretty sure that I filed a bug with Altera on this. But maybe not.