PR_GET_TID_ADDRESS2const

Usage

#include <linux/prctl.h>  /* Definition of PR_* constants */
#include <sys/prctl.h>

Library

Standard C library (libc, -lc)

Overview

Return the clear_child_tid address set by set_tid_address(2) and the clone(2) CLONE_CHILD_CLEARTID flag, in the location pointed to by addrp.

This feature is available only if the kernel is built with the CONFIG_CHECKPOINT_RESTORE option enabled.

Return value

On success, 0 is returned. On error, -1 is returned, and errno is set to indicate the error.

Errors

EFAULT

addrp is an invalid address.

Caveats

Note that since the prctl() system call does not have a compat implementation for the AMD64 x32 and MIPS n32 ABIs, and the kernel writes out a pointer using the kernel's pointer size, this operation expects a user-space buffer of 8 (not 4) bytes on these ABIs.