#include <linux/futex.h> #include <syscall.h> long get_robust_list(int pid, struct robust_list_head **head_ptr, size_t *len_ptr); long set_robust_list(struct robust_list_head *head, size_t len);
get_robust_list returns the head of the robust futex list of the thread with TID defined by the pid argument. If pid is 0, the returned head belongs to the current thread. head_ptr is the pointer to the head of the list of robust futexes. The get_robust_list function stores the address of the head of the list here. len_ptr is the pointer to the length variable. get_robust_list stores sizeof(**head_ptr) here.
set_robust_list sets the head of the list of robust futexes owned by the current thread to head. len is the size of *head.
The get_robust_list function fails with EPERM if the current process does not have permission to see the robust futex list of the thread with the TID pid, ESRCH if a thread with the TID pid does not exist, or EFAULT if the head of the robust futex list can't be stored in the space specified by the head argument.
The system call is only available for debugging purposes and is not needed for normal operations.
Both system calls are not available to application programs as functions; they can be called using the syscall(3) function.