osfmk/man/mach_port_set_seqno.html
Function - Change the current value of the target port's sequence number.
**kern\_return\_t mach\_port\_set\_seqno**** (ipc\_space\_t **task,** mach\_port\_name\_t **name,** mach\_port\_seqno\_t **seqno** );**
task[in task send right] The task owning the receive right.
name[in scalar] task's name for the receive right.
seqno[in scalar] The sequence number that the next message received from the port will have.
The mach_port_set_seqno function changes the sequence number of task's receive right named name.
(Each port is associated with a sequence number attribute that can be used to track the order in which messages sent to the port are received. A port's sequence number is initially set to zero and is incremented each time a message is received from the port. A port's sequence number is automatically reset to zero each time the port's receive right migrates.)
This interface is machine word length specific because of the port name parameter.
KERN_INVALID_NAME name did not denote a right.
KERN_INVALID_RIGHT name denoted a right, but not a receive right.
Functions: mach_port_get_attributes.