Hello Pavel,

On 04/27/2015 10:37 PM, Pavel Machek wrote:

Hi!

quoted

              The FUTEX_WAIT_OP operation is equivalent to execute the follow???
              ing  code  atomically  and totally ordered with respect to other
              futex operations on any of the two supplied futex words:

"to executing"?

Yep. Fixed.

quoted

              The  operation  and  comparison  that  are  to  be performed are
              encoded in the bits of  the  argument  val3.   Pictorially,  the
              encoding is:

                      +---+---+-----------+-----------+
                      |op |cmp|   oparg   |  cmparg   |
                      +---+---+-----------+-----------+
                        4   4       12          12    <== # of bits

:-)

quoted

RETURN VALUE
       In the event of an error, all operations return -1  and  set  errno  to
       indicate  the  cause of the error.  The return value on success depends
       on the operation, as described in the following list:

Did you say (at the begining) that there is no glibc wrapper?

Yes, this could be clearer. I changed it to

RETURN VALUE
       In the event of an error (and assuming that futex()  was  invoked
       via  syscall(2)), all operations return -1 and set errno to indi‐
       cate the cause of the error.

quoted

       EINVAL The operation in futex_op is one of those that employs  a  time???
              out,  but  the supplied timeout argument was invalid (tv_sec was
              less than zero, or tv_nsec was not less than 1000,000,000).

1,000...?

Fixed.

Thanks for the comments!

Cheers,

Michael


-- 
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/