| rax | 156 | set scheduling algorithm/parameters | 8 bit |
| rbx | pid | process identifire 0 for this calling process | 16 bit |
| rcx | policy | scheduling policy, one of: SCHED_OTHER = 0 SCHED_FIFO = 1 SCHED_RR = 2 | 16 bit |
| rdx | *p | pointer to priority | 16 bit |
| On return | rax |
| 0/errorcode |
| Errorcode | c++ name | Description |
| 1 | EPERM | Operation not permitted |
| 3 | ESRCH | No such process |
| 14 | EFAULT | Bad address |
| 22 | EINVAL | Invalid argument |