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PR_SVE_GET_VL(2const) — Linux manual page

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

PR_SVE_GET_VL(2const)                               PR_SVE_GET_VL(2const)

NAME         top

       PR_SVE_GET_VL - get the thread's SVE vector length

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

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

       int prctl(PR_SVE_GET_VL);

DESCRIPTION         top

       Get the thread's current SVE vector length configuration.

       This operation returns a nonnegative value that describes the
       current configuration.  The bits corresponding to
       PR_SVE_VL_LEN_MASK contain the currently configured vector length
       in bytes.  The bit corresponding to PR_SVE_VL_INHERIT indicates
       whether the vector length will be inherited across execve(2).

RETURN VALUE         top

       On success, PR_SVE_GET_VL, return the nonnegative values described
       above.  On error, -1 is returned, and errno is set to indicate the
       error.

ERRORS         top

       EINVAL SVE is not available on this platform.

STANDARDS         top

       Linux.  arm64 only.

HISTORY         top

       Linux 4.15 (arm64).

CAVEATS         top

       There is no way to determine whether there is a pending vector
       length change that has not yet taken effect.

SEE ALSO         top

       prctl(2), PR_SVE_SET_VL(2const)

       For more information, see the kernel source file
       Documentation/arm64/sve.rst (or Documentation/arm64/sve.txt before
       Linux 5.3).

COLOPHON         top

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

Pages that refer to this page: prctl(2),  PR_SVE_SET_VL(2const)

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