Provided by: linux-doc-2.6.15_2.6.15-23.39_all bug

NAME
       get_user - Get a simple variable from user space.


SYNOPSIS
       get_user  (x, ptr);


ARGUMENTS
       x      Variable to store result.

       ptr    Source address, in user space.


CONTEXT
       User context only. This function may sleep.


DESCRIPTION
       This  macro  copies  a single simple variable from user space to kernel
       space. It supports simple types like char and int, but not larger  data
       types like structures or arrays.

        ptr  must  have  pointer-to-simple-variable  type,  and  the result of
       dereferencing ptr must be assignable to x without a cast.

       Returns zero on success, or -EFAULT on error. On error, the variable  x
       is set to zero.