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PR_GET_TID_ADDRESS(2const) — Linux manual page

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | STANDARDS | HISTORY | CAVEATS | SEE ALSO | COLOPHON 

PR_GET_TID_ADDRESS(2const)                     PR_GET_TID_ADDRESS(2const)

NAME         top

       PR_GET_TID_ADDRESS - get the clear_child_tid address

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

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

       int prctl(PR_GET_TID_ADDRESS, int **addrp);

DESCRIPTION         top

       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         top

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

ERRORS         top

       EFAULT addrp is an invalid address.

STANDARDS         top

       Linux.

HISTORY         top

       Linux 3.5.

CAVEATS         top

       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.

SEE ALSO         top

       prctl(2)

COLOPHON         top

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Linux man-pages 6.15            2025-05-17     PR_GET_TID_ADDRESS(2const)

Pages that refer to this page: prctl(2)

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