POSIX mq_receive() call fails sporadically and sets errno EFAULT (,which is not documented for this call in QNX 
documentation)
  
In my application, I use a posix message queue which works fine without any issues, but very sporadically mq_receive 
call returns -1 and sets errno EFAULT (BAD ADDRESS).

The documentation of mq_receive doesn't specify that EFAULT errno is set. 

Could someone throw more light on this behavior of mq_receive?
Or if you think of scenarios in which cases EFAULT is set by mq_receive()?

Thanks in advance for any hints.