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KERNACC(9)		 BSD Kernel Developer's	Manual		    KERNACC(9)

NAME
     kernacc, useracc -- check memory regions for accessibility

SYNOPSIS
     #include <sys/param.h>
     #include <sys/proc.h>
     #include <vm/vm.h>
     #include <vm/vm_extern.h>

     int
     kernacc(void *addr, int len, int rw);

     int
     useracc(void *addr, int len, int rw);

DESCRIPTION
     The kernacc() and useracc() functions check whether operations of the
     type specified in rw are permitted	in the range of	virtual	addresses
     given by addr and len.  The possible values of rw are any bitwise combi-
     nation of VM_PROT_READ, VM_PROT_WRITE and VM_PROT_EXECUTE.	 kernacc()
     checks addresses in the kernel address space, while useracc() considers
     addr to represent an user space address.  The process context to use for
     this operation is taken from the global variable curproc.

RETURN VALUES
     Both functions return boolean true	if the type of access specified	by rw
     is	permitted.  Otherwise boolean false is returned.

BUGS
     The process pointer should	be passed in as	an argument to useracc().

BSD				 June 16, 1996				   BSD

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | BUGS

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