@node __djgpp_set_page_attributes, memory
@findex __djgpp_set_page_attributes
@subheading Syntax

@example
#include <dpmi.h>

int __djgpp_set_page_attributes(void *our_addr, unsigned long num_bytes,
			        unsigned short attributes);
@end example

@subheading Description

This function sets the DPMI page attributes for the pages in a range
of memory.  @var{our_addr} and @var{num_bytes} must be page-aligned.
If they are not page-aligned, @code{errno} will be set to @code{EINVAL}
and the routine will fail.

Consult DPMI documentation on function 0507H for the meaning of the
@var{attributes} argument.  Note: since 0507H is a DPMI service new
with DPMI 1.0, this call will fail on most DPMI 0.9 servers.  For your
program to work on a wide range of systems, you should not assume this
call will succeed.

Even on failure, this routine may affect a subset of the pages specified.

@subheading Return Value

0 on success, -1 on failure.  On failure, @code{errno} will be set to
@code{EINVAL} for illegal input parameters, or @code{EACCES} if the
DPMI server rejected the attribute setting.

@subheading Portability

@portability !ansi, !posix

@subheading Example

@example
if (__djgpp_set_page_attributes (my_page_aligned_memory, 16384, 0))
  printf ("Failed to make pages uncommitted!\n");
@end example