HP 3000 Manuals HP 3000 Manuals
The UNITCONTROL Procedure
The UNITCONTROL procedure enables a FORTRAN 77 program to request several
actions for any FORTRAN logical unit.
The UNITCONTROL procedure is called from an HP FORTRAN 77 program as
follows:
CALL UNITCONTROL(unit,opt)
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| Item | Description/Default | Restrictions |
| | | |
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| | | |
| unit | Positive integer (INTEGER*2 or INTEGER*4) that | Must be nonnegative. |
| | speccifies the unit number of the file to be | |
| | used. | |
| | | |
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| | | |
| opt | Integer (INTEGER*2 or INTEGER*4) that specifies | None. |
| | the option (see table 5-1). | |
| | | |
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The options for the UNITCONTROL intrinsic are listed in table 5-1.
Table 5-1. UNITCONTROL Options
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| Option | Description |
| | |
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| | |
| -1 | Rewind (but don't close file). |
| | |
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| 0 | Backspace. |
| | |
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| 1 | Write an EOF mark. |
| | |
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| | |
| 2 | Skip backward to a tape mark. |
| | |
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| 3 | Skip forward to a tape mark. |
| | |
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| 4 | Unload the tape and close the file. |
| | |
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| | |
| 5 | Leave the tape loaded and close the file. |
| | |
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| 6 | Convert the file to prespacing. |
| | |
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| | |
| 7 | Convert the file to postpacing. |
| | |
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| 8 | Close the file. |
| | |
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Refer to the HP FORTRAN 77/iX Programmer's Guide for an example of using
the UNITCONTROL intrinsic.