ACCESS_OK

Section: (9)
Updated: 17 July 2003
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NAME

access_ok - Checks if a user space pointer is valid  

SYNOPSIS

access_ok ( type, addr, size);  

ARGUMENTS

type
Type of access: VERIFY_READ or VERIFY_WRITE. Note that VERIFY_WRITE is a superset of VERIFY_READ - if it is safe to write to a block, it is always safe to read from it.
addr
User space pointer to start of block to check
size
Size of block to check
 

CONTEXT

User context only. This function may sleep.  

DESCRIPTION

Checks if a pointer to a block of memory in user space is valid.

Returns true (nonzero) if the memory block may be valid, false (zero) if it is definitely invalid.

Note that, depending on architecture, this function probably just checks that the pointer is in the user space range - after calling this function, memory access functions may still return -EFAULT.  

ABOUT THIS DOCUMENT

This documentation is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

For more details see the file COPYING in the source distribution of Linux.

If you have comments on the formatting of this manpage, then please contact Michael Still (mikal@stillhq.com).

This documentation was generated with kernel version 2.5.72.


 

Index

NAME
SYNOPSIS
ARGUMENTS
CONTEXT
DESCRIPTION
ABOUT THIS DOCUMENT

This document was created by man2html, using the manual pages.
Time: 02:49:54 GMT, July 17, 2003