fix syscall argument bug in pthread_getschedparam the address of the pointer to the sched param, rather than the pointer, was being passed to the kernel.
add support for thread scheduling (POSIX TPS option) linux's sched_* syscalls actually implement the TPS (thread scheduling) functionality, not the PS (process scheduling) functionality which the sched_* functions are supposed to have. omitting support for the PS option (and having the sched_* interfaces fail with ENOSYS rather than omitting them, since some broken software assumes they exist) seems to be the only conforming way to do this on linux.