HP 3000 Manuals HP 3000 Manuals
Permanent Files
A permanent file exists as a file in the system file domain. Its
existence is not limited to the duration of its creating job or session,
and depending on security restrictions, it may be accessed by jobs or
sessions other than the one that created it. Some or all of the space
for a permanent file has already been allocated, and its physical
characteristics have been defined.
Table 4-1. Features of New, Temporary, and Permanent Files
----------------------------------------------------------------------------------------------
| | | |
| New Files | Temporary Files | Permanent Files |
| | | |
----------------------------------------------------------------------------------------------
| | | |
| Exists only to creating | Exists as job temporary | Exists as permanent file in |
| process. | file. | system. |
| | | |
| Space not allocated yet. | Space (some or all) already | Space (some or all) already |
| | allocated. | allocated. |
| | | |
| Physical characteristics not | Physical characteristics | Physical characteristics |
| previously defined. | defined. | defined. |
| | | |
| Known only to creating job | Known only to creating job | Known system-wide. |
| or session. | or session. | |
| | | |
| Exists only for duration of | Exists only for duration of | Permanent. |
| program execution. | creating job/session. | |
| | | |
----------------------------------------------------------------------------------------------
Table 4-2. File Domains Permitted
---------------------------------------------------------------------------------------------
| | |
| Device Type | Domain Permitted |
| | |
---------------------------------------------------------------------------------------------
| | |
| Disk | new, temporary, or permanent |
| | |
| Magnetic Tape Device | new * or permanent |
| | |
| Synchronous Single-Line Controller | new * or permanent |
| | |
| Programmable Controller | new * or permanent |
| | |
| Terminal | new * or permanent |
| | |
| Line Printer | new * |
| | |
| Plotter | new * |
| | |
---------------------------------------------------------------------------------------------
The features of new, temporary and permanent files are listed in Table
4-1 .
In some cases, the domain you can specify for a file may be restricted by
the type of device on which the file resides. The domains permitted are
summarized in Table 4-2 .
NOTE * When you specify a file domain using HPFOPEN, you should open
only disk files with the domain option set to NEW. Device files can
be opened with the domain option set to NEW (to maintain
compatibility with with MPE V/E), but a warning is returned in the
status parameter.