tpf_ndsp_unmark: Unmark a nondisplayable storage area

This function unmarks the specified storage area so that it is no longer nondisplayable.

Last updated

  • Changed for PUT07 (information only; no code change).
  • Added for PUT05.

Format

#include <tpf/indsp.h>
int      tpf_ndsp_unmark(void * address, int length);
address
A pointer to the start of the storage area.
length
The length of the storage area in bytes.

Normal return

The following is returned:
ndsrunorm
The specified storage area was unmarked and is no longer nondisplayable.

Error return

None.

Programming considerations

  • Use the tpf_ndsp_mark function to unmark a storage area so that it is no longer nondisplayable.
  • If an area is marked multiple times, you can unmark the area with a single unmark request. You do not have to issue an unmark request for each previous mark request. That is, the tpf_ndsp_mark and tpf_ndsp_unmark functions stack and unstack marked status.
  • You can specify a storage area that already is fully or partially unmarked. Any marked portions of the specified storage area will be unmarked and any unmarked portions of the specified storage area will remain unmarked.

Examples

#include <tpf/indsp.h>

:
char  *  buff = (char*)malloc(0x20000);

//Mark the storage as non-displayable
rc = tpf_ndsp_mark(addr,len);
if(rc != ndsrmnorm)
{
   //error handling here
   free(buff);
}

//Do something here with marked storage, then unmark
:
tpf_ndsp_unmark(addr,len);

free(buff);
:

Related information

tpf_ndsp_mark: Mark a storage area as nondisplayable.

For more information about nondisplayable storage, see z/TPF Security.

For information about the NDSPC macro, see z/TPF General Services.

For more information about z/TPF C/C++ language support, see z/TPF C functions overview.