SET_THREAD_AREA(2) Linux Programmer's Manual SET_THREAD_AREA(2)NAMEset_thread_area - set a thread local storage (TLS) area
int set_thread_area(struct user_desc *u_info);
Note: There is no glibc wrapper for this system call; see NOTES.
DESCRIPTIONset_thread_area() sets an entry in the current thread's thread-local
storage (TLS) array. The TLS array entry set by set_thread_area() cor‐
responds to the value of u_info->entry_number passed in by the user.
If this value is in bounds, set_thread_area() copies the TLS descriptor
pointed to by u_info into the thread's TLS array.
When set_thread_area() is passed an entry_number of -1, it uses a free
TLS entry. If set_thread_area() finds a free TLS entry, the value of
u_info->entry_number is set upon return to show which entry was
RETURN VALUEset_thread_area() returns 0 on success, and -1 on failure, with errno
EINVAL u_info->entry_number is out of bounds.
EFAULT u_info is an invalid pointer.
ESRCH A free TLS entry could not be located.
A version of set_thread_area() first appeared in Linux 2.5.29.
CONFORMING TOset_thread_area() is Linux-specific and should not be used in programs
that are intended to be portable.
Glibc does not provide a wrapper for this system call, since it is gen‐
erally intended only for use by threading libraries. In the unlikely
event that you want to call it directly, use syscall(2).
This page is part of release 3.65 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 SET_THREAD_AREA(2)