returns the message queue identifier associated with
A message queue identifier is a unique integer greater than zero.
A message queue is created if either
is equal to
does not have a message queue identifier associated with it, and the
bit is set in
If a new message queue is created, the data structure associated with it (the
is initialized as follows:
are set to the effective uid of the calling process.
are set to the effective gid of the calling process.
is set to the lower 9 bits of
which are set by ORing these constants:
Read access for user.
Write access for user.
Read access for group.
Write access for group.
Read access for other.
Write access for other.
are set to 0.
is set to the system wide maximum value for the number of bytes in a queue
is set to the current time.