HP 3000 Manuals HP 3000 Manuals
Using the File Handling Procedures
This section describes the FSET, FNUM, and UNITCONTROL procedures. Refer
to the HP FORTRAN 77/iX Reference Manual for more details on these
procedures.
FSET Procedure
The FSET procedure changes the MPE/iX operating system file number
assigned to a given FORTRAN logical unit number in the file table.
The FSET procedure can be called from a FORTRAN 77 program as follows:
CALL FSET(unit,newfile,oldfile)
------------------------------------------------------------------------------
| | | |
| Item | Description/Default | Restrictions |
| | | |
------------------------------------------------------------------------------
| | | |
| unit | Positive integer constant or | Must be nonnegative. |
| | variable (INTEGER*2 or | |
| | INTEGER*4) that specifies the | |
| | FORTRAN file unit for which the | |
| | change is to be made. | |
| | | |
------------------------------------------------------------------------------
| | | |
| newfile | Positive integer constant or | Must be nonnegative. |
| | variable (INTEGER*2 or | |
| | INTEGER*4) that specifies the | |
| | new MPE/iX file number to be | |
| | assigned to unit. | |
| | | |
------------------------------------------------------------------------------
| | | |
| oldfile | Integer variable to which the | Cannot be the same |
| | procedure returns the old value | variable as newfile. |
| | of the file number that was | |
| | assigned to unit. | |
| | | |
------------------------------------------------------------------------------
The following program shows how to use the FSET procedure to assign a
FORTRAN logical unit number.
$WARNINGS OFF
$SHORT
PROGRAM fset_example
C
C FOPEN, FSET, and FCLOSE Example
IMPLICIT NONE
INTEGER filenumber,oldnum
SYSTEM INTRINSIC FOPEN,FCLOSE
CHARACTER buffer*72,filename*16
PARAMETER (FILENAME = 'maillist')
filenumber = FOPEN(filename,1B,105B)
IF (ccode())30,10,30
C Call FSET to assign the FORTRAN unit number five to "filenumber"
10 CALL FSET(5,filenumber,oldnum)
PRINT *,'Old file number = ',oldnum
PRINT *,'FOPEN number = ',filenumber
20 READ(5, '(A72)' ,END=40)buffer ! Read to EOF
WRITE(6,100)buffer(1:19)
100 FORMAT(T2,A20)
GO TO 20
30 PRINT *,'Could not open file'
STOP
C Close the file
40 CALL FCLOSE(filenumber,1B,0B)
IF (ccode())50,60,50
50 PRINT *,'Could not close file'
STOP
60 PRINT *,'File closed successfully'
STOP
END
This is the output of the program:
Old file number = 11
FOPEN number = 10
SMILEY FACE
MICKEY MOUSE
SLIM JIM
CHARITY BELL
DONALD DUCK
JOE SMOE
CLAIRE PLIMSOL
INDIANA JONES
JAKE FAKE
File closed successfully
FNUM Procedure
The FNUM procedure returns the MPE/iX system file number assigned to a
given FORTRAN 77 logical unit number. This procedure returns an
INTEGER*2 or INTEGER*4 value.
The FNUM procedure can be called from an HP FORTRAN 77/iX program as an
external function as follows:
I = FNUM(unit)
------------------------------------------------------------------------------------
| | | |
| Item | Description/Default | Restrictions |
| | | |
------------------------------------------------------------------------------------
| | | |
| unit | Positive integer (INTEGER*2 or | Must be nonnegative. |
| | INTEGER*4) that specifies the FORTRAN | |
| | file unit for which the MPE/iX system | |
| | file number is to be extracted. The | |
| | value returned is the same size as the | |
| | argument. | |
| | | |
------------------------------------------------------------------------------------
See the UNITCONTROL procedure description below for an example of using
the FNUM procedure.
UNITCONTROL Procedure
The UNITCONTROL procedure allows an HP FORTRAN 77/iX program to request
several actions (see below) for any FORTRAN 77 logical unit.
The UNITCONTROL procedure is called as follows:
CALL UNITCONTROL(unit,opt)
------------------------------------------------------------------------------------
| | | |
| Item | Description/Default | Restrictions |
| | | |
------------------------------------------------------------------------------------
| | | |
| unit | Positive integer (INTEGER*2 or | Must be nonnegative. |
| | INTEGER*4) that specifies the unit | |
| | number of the file to be used. | |
| | | |
------------------------------------------------------------------------------------
| | | |
| opt | Integer (INTEGER*2 or INTEGER*4) that | None. |
| | specifies the option (see Table 4-1). | |
| | | |
------------------------------------------------------------------------------------
The options for the UNITCONTROL intrinsic are listed in Table 4-1 .
Table 4-1. UNITCONTROL Options
---------------------------------------------------------
| | |
| Option | Description |
| | |
---------------------------------------------------------
| | |
| -1 | Rewind (but don't close the file) |
| | |
| 0 | Backspace |
| | |
| 1 | Write an EOF mark. |
| | |
| 2 | Skip backward to a tape mark |
| | |
| 3 | Skip forward to a tape mark |
| | |
| 4 | Unload the tape and close the file |
| | |
| 5 | Leave the tape loaded and close the |
| | file |
| | |
| 6 | Convert the file to prespacing |
| | |
| 7 | Convert the file to postspacing |
| | |
| 8 | Close the file |
| | |
---------------------------------------------------------
NOTE Use the REWIND, BACKSPACE, ENDFILE, and CLOSE statements instead of
the -1, 0, 1, and 8 options. These statements are part of the
FORTRAN 77 language and are more portable.
Option values outside the range of -1 through 8 are ignored and no
action is taken.
The program below shows how to use the FNUM and UNITCONTROL procedures.
The SHORT compiler directive forces the integer and logical default size
to two bytes.
$WARNINGS OFF
$SHORT
PROGRAM unit_fnum_ex
C Example program using FNUM and UNITCONTROL
IMPLICIT NONE
SYSTEM INTRINSIC HPMERGEINIT
CHARACTER buffer*72
INTEGER*4 keysonly,numkeys,keys(8),infiles(3),status
INTEGER*4 outputfile(2),error
C Merge two sorted files, MAIL1 (unit 20) and MAIL2 (unit 21)
C into a third file, MAIL3 (unit 22)
C Open all files
OPEN(20,FILE='mail1',STATUS='OLD',ERR=200)
OPEN(21,FILE='mail2',STATUS='OLD',ERR=300)
OPEN(22,FILE='mail3',STATUS='NEW',ERR=400)
C Establish keys for SORT - major at column 11 for 9 bytes
C (LAST NAME) and minor at column 1 for 10 bytes (FIRST NAME)
keys(1) = 11
keys(2) = 9
keys(3) = 10
keys(4) = 0
keys(5) = 1
keys(6) = 10
keys(7) = 10
keys(8) = 0
keysonly = 0
numkeys = 2
C Establish MPE/iX filenumbers for input files (MAIL1 and MAIL2)
C by referencing the FNUM procedure
infiles(1) = FNUM(20)
infiles(2) = FNUM(21)
infiles(3) = 0
C Establish MPE/iX filenumbers for output file (MAIL3) by
C referencing the FNUM procedure
outputfile(1) = FNUM(22)
outputfile(2) = 0
C Merge the files
CALL HPMERGEINIT(status,infiles,,outputfile,,
> keysonly,numkeys,keys,,,,,error)
IF (error .NE. 0) STOP 'Merge failed'
C Display the new merged file
REWIND 22
20 READ(22,'(A72)',END=30) buffer
WRITE(6,100)buffer
100 FORMAT(T2,A)
GO TO 20
C Call UNITCONTROL to close the files MAIL1, MAIL2, and MAIL3,
C which is the same as using the CLOSE statement
30 CALL UNITCONTROL(20,8)
CALL UNITCONTROL(21,8)
CALL UNITCONTROL(22,8)
STOP
200 PRINT *,'Could not open file - MAIL1'
STOP
300 PRINT *,'Could not open file - MAIL2'
STOP
400 PRINT *,'Could not open output file - MAIL3'
END
This is the output of the program:
PLAINS ANTELOPE 201 OPENSPACE AVE BIGCOUNTRY WY
LOIS ANYONE 6190 COURT ST METROPOLIS NY
KING ARTHUR 329 EXCALIBUR ST CAMELOT CA
ALI BABA 40 THIEVES WAY SESAME CO
BLACK BEAR 47 ALLOVER DR ANYWHERE US
JOHN BIGTOWN 965 APPIAN WAY METROPOLIS NY
KNEE BUCKLER 974 FISTICUFF DR PUGILIST ND
SWASH BUCKLER 497 PLAYACTING CT MOVIETOWN CA
ANIMAL CRACKERS 1000 CRUNCH LN COOKIE US
MULE DEER 963 FOREST PL HIGHCOUNTRY CA
WHITETAIL DEER 34 WOODSY PL BACKCOUNTRY ME
JAMES DOE 4193 ANY ST ANYTOWN MD
JANE DOE 3959 TREEWOOD LN BIGTOWN MA
PRAIRIE DOG 493 ROLLINGHILLS DR OPENSPACE ND
JOHN DOUGHE 239 MAIN ST HOMETOWN MA
MALLARD DUCK 79 MARSH PL PUDDLEDUCK CA
JENNA GRANDTR 493 TWENTIETH ST PROGRESSIVE CA
KARISSA GRANDTR 7917 BROADMOOR WAY BIGTOWN MA
SNOWSHOE HARE 742 FRIGID WAY COLDSPOT MN
MOUNTAIN LION 796 KING DR THICKET NM
SPACE MANN 9999 GALAXY WAY UNIVERSE CA
SWAMP RABBIT 4444 DAMPLACE RD BAYOU LO
NASTY RATTLER 243 DANGER AVE DESERTVILLE CA
BIGHORN SHEEP 999 MOUNTAIN DR HIGHPLACE CO
GREY SQUIRREL 432 PLEASANT DR FALLCOLORS MA