prctl(2)                      System Calls Manual                     prctl(2)

<?><?><?><?><?><?><?><?><?><?><?><?>
       prctl - operations on a process or thread

<?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?> C (libc, -lc)

<?><?><?><?><?>
       #include <linux/prctl.h>  /* <?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?> PR_* */
       #include <sys/prctl.h>

       int prctl(int op, ...);

<?><?><?><?><?><?><?><?>
       prctl()  manipulates various aspects of the behavior of the calling
       thread or process.

       prctl()  is called with a first argument describing what to do, and
       further arguments with a significance depending on the first one.  The
       first argument can be:

       PR_CAP_AMBIENT
       PR_CAPBSET_READ
       PR_CAPBSET_DROP
       PR_SET_CHILD_SUBREAPER
       PR_GET_CHILD_SUBREAPER
       PR_SET_DUMPABLE
       PR_GET_DUMPABLE
       PR_SET_ENDIAN
       PR_GET_ENDIAN
       PR_SET_FP_MODE
       PR_GET_FP_MODE
       PR_SET_FPEMU
       PR_GET_FPEMU
       PR_SET_FPEXC
       PR_GET_FPEXC
       PR_SET_IO_FLUSHER
       PR_GET_IO_FLUSHER
       PR_SET_KEEPCAPS
       PR_GET_KEEPCAPS
       PR_MCE_KILL
       PR_MCE_KILL_GET
       PR_SET_MM
       PR_SET_VMA
       PR_MPX_ENABLE_MANAGEMENT
       PR_MPX_DISABLE_MANAGEMENT
       PR_SET_NAME
       PR_GET_NAME
       PR_SET_NO_NEW_PRIVS
       PR_GET_NO_NEW_PRIVS
       PR_PAC_RESET_KEYS
       PR_SET_PDEATHSIG
       PR_GET_PDEATHSIG
       PR_SET_PTRACER
       PR_SET_SECCOMP
       PR_GET_SECCOMP
       PR_SET_SECUREBITS
       PR_GET_SECUREBITS
       PR_GET_SPECULATION_CTRL
       PR_SET_SPECULATION_CTRL
       PR_SVE_SET_VL
       PR_SVE_GET_VL
       PR_SET_SYSCALL_USER_DISPATCH
       PR_SET_TAGGED_ADDR_CTRL
       PR_GET_TAGGED_ADDR_CTRL
       PR_TASK_PERF_EVENTS_DISABLE
       PR_TASK_PERF_EVENTS_ENABLE
       PR_SET_THP_DISABLE
       PR_GET_THP_DISABLE
       PR_GET_TID_ADDRESS
       PR_SET_TIMERSLACK
       PR_GET_TIMERSLACK
       PR_SET_TIMING
       PR_GET_TIMING
       PR_SET_TSC
       PR_GET_TSC
       PR_SET_UNALIGN
       PR_GET_UNALIGN
       PR_GET_AUXV
       PR_SET_MDWE
       PR_GET_MDWE
       PR_RISCV_SET_ICACHE_FLUSH_CTX
       PR_FUTEX_HASH

<?><?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?>
       <?> <?><?><?><?><?><?> <?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?>.
       <?> <?><?><?><?><?><?> <?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?><?> -1, <?> errno
       <?><?><?><?><?><?><?><?><?><?><?><?><?><?><?> <?><?><?>
       <?><?><?><?><?><?><?><?> <?><?><?><?><?><?>.

<?><?><?><?><?><?>
       EINVAL The value of op is not recognized, or not supported on this
              system.

       EINVAL An unused argument is nonzero.

<?><?><?><?><?><?>
       IRIX has a prctl()  system call (also introduced in Linux 2.1.44 as
       irix_prctl on the MIPS architecture), with prototype

           ptrdiff_t prctl(int op, int arg2, int arg3);

       and operations to get the maximum number of processes per user, get the
       maximum number of processors the calling process can use, find out
       whether a specified process is currently blocked, get or set the
       maximum stack size, and so on.

<?><?><?><?><?><?><?><?><?>
       Linux.

<?><?><?><?><?><?><?>
       Linux 2.1.57, glibc 2.0.6

CAVEATS
       The prototype of the libc wrapper uses a variadic argument list.  This
       makes it necessary to pass the arguments with the right width.  When
       passing numeric constants, such as 0, use a suffix: 0L.

       Careless use of some prctl()  operations can confuse the user-space
       run-time environment, so these operations should be used with care.

<?><?><?><?><?><?><?><?> <?><?><?><?><?>
       signal(2), PR_CAP_AMBIENT(2const), PR_CAPBSET_READ(2const),
       PR_CAPBSET_DROP(2const), PR_SET_CHILD_SUBREAPER(2const),
       PR_GET_CHILD_SUBREAPER(2const), PR_SET_DUMPABLE(2const),
       PR_GET_DUMPABLE(2const), PR_SET_ENDIAN(2const), PR_GET_ENDIAN(2const),
       PR_SET_FP_MODE(2const), PR_GET_FP_MODE(2const), PR_SET_FPEMU(2const),
       PR_GET_FPEMU(2const), PR_SET_FPEXC(2const), PR_GET_FPEXC(2const),
       PR_SET_IO_FLUSHER(2const), PR_GET_IO_FLUSHER(2const),
       PR_SET_KEEPCAPS(2const), PR_GET_KEEPCAPS(2const), PR_MCE_KILL(2const),
       PR_MCE_KILL_GET(2const), PR_SET_MM(2const), PR_SET_VMA(2const),
       PR_MPX_ENABLE_MANAGEMENT(2const), PR_MPX_DISABLE_MANAGEMENT(2const),
       PR_SET_NAME(2const), PR_GET_NAME(2const), PR_SET_NO_NEW_PRIVS(2const),
       PR_GET_NO_NEW_PRIVS(2const), PR_PAC_RESET_KEYS(2const),
       PR_SET_PDEATHSIG(2const), PR_GET_PDEATHSIG(2const),
       PR_SET_PTRACER(2const), PR_SET_SECCOMP(2const), PR_GET_SECCOMP(2const),
       PR_SET_SECUREBITS(2const), PR_GET_SECUREBITS(2const),
       PR_SET_SPECULATION_CTRL(2const), PR_GET_SPECULATION_CTRL(2const),
       PR_SVE_SET_VL(2const), PR_SVE_GET_VL(2const),
       PR_SET_SYSCALL_USER_DISPATCH(2const), PR_SET_TAGGED_ADDR_CTRL(2const),
       PR_GET_TAGGED_ADDR_CTRL(2const), PR_TASK_PERF_EVENTS_DISABLE(2const),
       PR_TASK_PERF_EVENTS_ENABLE(2const), PR_SET_THP_DISABLE(2const),
       PR_GET_THP_DISABLE(2const), PR_GET_TID_ADDRESS(2const),
       PR_SET_TIMERSLACK(2const), PR_GET_TIMERSLACK(2const),
       PR_SET_TIMING(2const), PR_GET_TIMING(2const), PR_SET_TSC(2const),
       PR_GET_TSC(2const), PR_SET_UNALIGN(2const), PR_GET_UNALIGN(2const),
       PR_GET_AUXV(2const), PR_SET_MDWE(2const), PR_GET_MDWE(2const),
       PR_RISCV_SET_ICACHE_FLUSH_CTX(2const), PR_FUTEX_HASH(2const), core(5)

<?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?> <?><?><?><?><?><?><?> <?><?><?><?>
       <?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?>(<?>) Alexey, Azamat Hackimov
       <azamat.hackimov@gmail.com>, kogamatranslator49 <r.podarov@yandex.ru>,
       Darima Kogan <silverdk99@gmail.com>, Max Is <ismax799@gmail.com>, Yuri
       Kozlov <yuray@komyakino.ru>, <?><?><?><?> <?><?><?><?><?><?>
       <pavia00@gmail.com> <?> Kirill Rekhov <krekhov.dev@gmail.com>

       <?><?><?><?> <?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?><?><?>; <?><?>
       <?><?><?><?><?><?><?><?><?><?><?><?><?><?><?><?> <?><?>
       <?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?> GNU (GNU General Public License - GPL,
       <https://www.gnu.org/licenses/gpl-3.0.html> <?><?><?><?><?><?> 3
       <?><?><?> <?><?><?><?><?> <?><?><?><?><?><?><?>) <?>
       <?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?>, <?><?> <?><?><?> <?><?><?><?><?>-<?><?><?><?>
       <?><?><?><?><?><?><?><?>.

       <?><?><?><?> <?><?> <?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?>-<?><?><?><?> <?><?><?><?><?><?> <?>
       <?><?><?><?><?><?><?><?> <?><?><?><?> <?><?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?>, <?><?><?><?><?><?><?><?><?><?>,
       <?><?><?><?><?><?><?><?> <?><?> <?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?><?>(<?><?>) <?><?> <?><?><?>(<?><?>)
       <?><?><?><?><?><?>(<?><?>) <?><?><?><?><?><?><?><?><?><?><?>
       <?><?><?><?><?> <?><?><?> <?><?> <?><?><?><?><?><?> <?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?>
       <?><?><?><?><?><?><?><?><?><?><?><?>
       <<debian-l10n-russian@lists.debian.org>>.

<?><?><?><?><?><?><?><?><?><?> <?><?><?><?><?><?><?><?> Linux 6.15
                           11 <?><?><?><?> 2025 <?>.                  prctl(2)