- ...here.
- See ADAM Programmer Note 7
for a description of these routines.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ...reside.
- On
Starlink systems this directory will normally be called
/star/starlink/lib/hds.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ...program.
- This
will work even if the object was originally created on a different
computer which formats its numbers differently.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ..."mapping".
- This terminology derives from the
facility provided by some operating systems for mapping the
contents of files into the computer's memory, so that they appear as
if they are arrays of numbers directly accessible to a
program. Although HDS exploits this technique when available, other
techniques can also be used to simulate this behaviour, so HDS does
not depend on the operating system providing this facility.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ...facility,
- This technique works because Fortran normally
passes the address of an array to a subroutine, so the routine is
fooled into thinking it's getting an array.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ...function
- We illustrate the
use of the CNF_PVAL function in this
document, although in most existing software which calls HDS this
function is not used. It has been introduced because of the
possibility that Fortran software which stores pointers in 32-bit
INTEGERs may need to execute in circumstances where 64 bits are
required to store a memory pointer. The purpose of the CNF_PVAL
function is then to expand the pointer value out to its full size
before use, if necessary. On currently-supported platforms, this step
is not normally needed, so use of CNF_PVAL may considered
optional. However, its inclusion in new software is recommended as a
useful precaution.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ...DAT__NOLOC
- As defined in the include file DAT_PAR.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ...invalid).
- You are advised not to depend on this
mechanism for annulling secondary locators because you will not
normally have complete control over a file's reference count (for
instance, it may be opened independently for some other purpose in the
same piece of software).
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ...blocks.
- An HDS block is 512 bytes.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ...blocks
- An HDS block is 512
bytes.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ...blocks
- An HDS block
is 512 bytes.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ...blocks
- An
HDS block is 512 bytes.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ...libraries
- On non-Starlink systems you may need to
specify a different directory if you have not installed the Starlink
software in the standard place.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ...characters
- That is,
anything except alphanumeric characters, slash `/', period `.',
underscore `_' and minus `-'.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.