The :FILE command cannot override at run time
any specifications in the disc file label for an existing disc file.
(The file label specifies physical characteristics of the file;
record structure, file structure, file code, and actual file name.)
Anything in the disc file label has precedence.
Similarly, device characteristics always prevail over
a :FILE command invoked for a device file.
:FILE can override the following:
Specifications that are not in a file label for a disc file.
Specifications that are not already given for a device file.
Specifications given when an intrinsic in the program opens the file.
If the program creates a disc file at run time, then
:FILE can override
the opening characteristics that the program was compiled to use
and create a file with different characteristics.
It is possible to use an intrinsic such as HPFOPEN or
FOPEN to override file equations.
When an intrinsic is set up to do this, the file equation produced
by invoking :FILE can be ignored unless the file name given in the
intrinsic opening the file is dereferenced (preceded by an asterisk (*)).
For detailed information on the hierarchy of overrides,
and for information on how this applies to labeled tapes, refer to
Accessing Files Programmer's Guide (32650-90017).
When a :FILE command is entered that contradicts some of
the HPFOPEN or FOPEN parameters for a file, The File System
maintains a hierarchy of overrides, as shown in Figure 6-11 “File System Hierarchy of Overrides”.
Figure 6-11 File System Hierarchy of Overrides
![[File System Hierarchy of Overrides]](img/f0611.gif)
