PR_SET_UNALIGN(2const)

NAME

PR_SET_UNALIGN - set unaligned access control bits

LIBRARY

Standard C library (libc, -lc)

SYNOPSIS

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

int prctl(PR_SET_UNALIGN, unsigned long flag);

DESCRIPTION

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

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

ERRORS

EINVAL: flag is not a valid value.

STANDARDS

Linux.

HISTORY

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