PR_SET_UNALIGN(2const) — Linux manual page

PR_SET_UNALIGN(2const)                            PR_SET_UNALIGN(2const)

NAME         top

       PR_SET_UNALIGN - set unaligned access control bits

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

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

       int prctl(PR_SET_UNALIGN, unsigned long flag);

DESCRIPTION         top

       Set unaligned access control bits to arg2.

       Pass PR_UNALIGN_NOPRINT to silently fix up unaligned user
       accesses, or PR_UNALIGN_SIGBUS to generate SIGBUS on unaligned
       user access.

       Alpha also supports an additional flag with the value of 4 and no
       corresponding named constant, which instructs kernel to not fix
       up unaligned accesses (it is analogous to providing the UAC_NOFIX
       flag in SSI_NVPAIRS operation of the setsysinfo() system call on
       Tru64).

RETURN VALUE         top

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

ERRORS         top

       EINVAL flag is not a valid value.

STANDARDS         top

       Linux.

HISTORY         top

       Only on:

       •  ia64, since Linux 2.3.48
       •  parisc, since Linux 2.6.15
       •  PowerPC, since Linux 2.6.18
       •  Alpha, since Linux 2.6.22
       •  sh, since Linux 2.6.34
       •  tile, since Linux 3.12

SEE ALSO         top

       prctl(2), PR_GET_UNALIGN(2const)

COLOPHON         top

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Linux man-pages 6.9.1          2024-06-02         PR_SET_UNALIGN(2const)

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

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