ukey_getkey Subroutine

Purpose

Queries the user-key for application memory.

Syntax

#include <sys/ukeys.h> int ukey_getkey (void * addr, ukey_t * ukey)

Description

The ukey_getkey subroutine can be used to determine the user-key associated with a memory address. The user-key returned by this service normally corresponds to the values set by the ukey_protect subroutine.

When an application memory can not have its user-key altered or is not part of the application address space. A user-key value of the UKEY_SYSTEM is returned for this memory.

Parameters

Item	Description
addr	Specifies the address of the region to be queried.
ukey	Value for the user-mode storage-key is returned here.

Return Values

When successful, the ukey_getkey subroutine returns a value of 0. Otherwise, it returns a value of -1 and sets the errno global variable to indicate the error.

Error Codes

If the ukey_getkey subroutine is unsuccessful, the errno global variable might be set to one of the following values:

Item	Description
EFAULT	A part of the buffer pointed to by the ukey parameter is out of range or otherwise inaccessible.
ENOMEM	Address is not valid for the address space of the process.
ENOSYS	User-keys are not supported.