osf1 man page for is_seg0_va

IS_KSEG_VA(9r)															    IS_KSEG_VA(9r)

NAME
       IS_KSEG_VA, IS_SEG0_VA, IS_SEG1_VA - General: Determine if the specified address is located in the kernel-unmapped address space, the user-
       mapped address space, and the kernel-mapped address space.

SYNOPSIS
       void IS_KSEG_VA(
	       unsigned long addr ); void IS_SEG0_VA(
	       unsigned long addr ); void IS_SEG1_VA(
	       unsigned long addr );

ARGUMENTS
       Specifies the virtual address.

DESCRIPTION
       The IS_KSEG_VA routine determines if the specified address is located in the kernel-unmapped address space. The IS_SEG0_VA  routine  deter-
       mines  if  the specified address is located in the user-mapped address space. The IS_SEG1_VA routine determines if the specified address is
       located in the kernel-mapped address space.

RETURN VALUES
       None

EXAMPLE
       The following code fragment shows a call to IS_KSEG_VA:

       .  .  .

       caddr_t virt_addr;  [1] unsigned phys_addr; [2]

       .  .  .

	   if(IS_KSEG_VA(virt_addr)) { [3]
	       phys_addr = KSEG_TO_PHYS(virt_addr); [4]

       .  .  .

       Declares a variable to store the user  buffer's	virtual  address.   Declares  a  variable  to  store  the  physical  address  returned	by
       KSEG_TO_PHYS.  Before calling KSEG_TO_PHYS, calls IS_KSEG_VA to determine if the virtual address is from the kernel-unmapped address space.
       If the virtual address is from the kernel-unmapped address space, then calls KSEG_TO_PHYS to convert the address to a corresponding  physi-
       cal address.

SEE ALSO
       Routines: KSEG_TO_PHYS(9r), PHYS_TO_KSEG(9r)

																    IS_KSEG_VA(9r)