NAME
getrobustlist, setrobustlist - get/set list of robust futexes SYNOPSIS
#include
#include
long getrobustlist(int pid, struct robustlisthead **headptr, sizet *lenptr); long setrobustlist(struct robustlisthead *head, sizet len); Note: There are no glibc wrappers for these system calls; see NOTES. DESCRIPTION The robust futex implementation needs to maintain per-thread lists of robust futexes which are unlocked when the thread exits. These lists are managed in user space; the kernel is notified about only the loca‐ tion of the head of the list. The getrobustlist() system call returns the head of the robust futex list of the thread whose thread ID is specified in pid. If pid is 0, the head of the list for the calling thread is returned. The list head is stored in the location pointed to by headptr. The size of the object pointed to by **headptr is stored in lenptr. The setrobustlist() system call requests the kernel to record the head of the list of robust futexes owned by the calling thread. The head argument is the list head to record. The len argument should be sizeof(*head). RETURN VALUE The setrobustlist() and getrobustlist() system calls return zero when the operation is successful, an error code otherwise. ERRORS The setrobustlist() system call can fail with the following error: EINVAL len does not match the size of structure struct robustlisthead expected by kernel. The getrobustlist() system call can fail with the following errors: EPERM The calling process does not have permission to see the robust futex list of the thread with the thread ID pid, and does not have the CAPSYSPTRACE capability. ESRCH No thread with the thread ID pid could be found. EFAULT The head of the robust futex list can't be stored at the loca‐ tion head. VERSIONS These system calls were added in Linux 2.6.17. No library support is provided; use syscall(2). NOTES These system calls are not needed by normal applications. No support for them is provided in glibc. In the unlikely event that you want to call them directly, use syscall(2). A thread can have only one robust futex list; therefore applications that wish to use this functionality should use the robust mutexes pro‐ vided by glibc. SEE ALSO futex(2)
Documentation/robust-futexes.txt and Documentation/robust-futex-ABI.txt in the Linux kernel source tree COLOPHON
This page is part of release 3.53 of the Linux man-pages project. A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
Linux 2012-07-13 GETROBUSTLIST(2)