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Conference turris::fortran

Title:Digital Fortran
Notice:Read notes 1.* for important information
Moderator:QUARK::LIONEL
Created:Thu Jun 01 1995
Last Modified:Fri Jun 06 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:1333
Total number of notes:6734

1261.0. "More F90 Questions!" by RHETT::HALETKY () Wed Apr 16 1997 11:49

    Hello,
    
    SOme more custoemr questions about Fortran:
    
    1) Does DEC Fortran permit access to a 64-bit unsigned integer data
    type? Also (or perhaps this is the same question in disguise), does DEC
    Fortran have an intrinsic function to access the UMULH instruction 
    (upper half of 64 x 64-bit unsigned integer multiplication)?
    
    2) Ever since I upgraded to OSF V3.2, My Fortran programs which read from
    and write to file don't do this properly unless I include the FULL pathname
    (they used to write to the directory from which the program was started
    by default). Also, the Unix "./{file}" local file specifier won't work
    -
    I have to open a file, e.g. using
    
            open(1,file='/usr/users/joe_blow/myfile.dat',status='unknown')
    
    
    Best regards,
    Ed Haletky
    Digital CSC
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1261.1answers to question #1TLE::WHITLOCKStan WhitlockWed Apr 16 1997 12:4813
>>    1) Does DEC Fortran permit access to a 64-bit unsigned integer data
>>    type? Also (or perhaps this is the same question in disguise), does DEC
>>    Fortran have an intrinsic function to access the UMULH instruction 
>>    (upper half of 64 x 64-bit unsigned integer multiplication)?
    
DF's INTEGER*8 data type is signed 64-bit integer.  DF has no data type that
maps into unsigned integer of any size.

At present there is no Fortran construct that generates a UMULH instruction.
In a future release {By the end of the calendar year}, there will be an
intrinsic called MULT_HIGH that generats a UMULH inline.

/Stan
1261.2#2 works for me - more info, pleaseTLE::WHITLOCKStan WhitlockWed Apr 16 1997 13:0325
>>  2) Ever since I upgraded to OSF V3.2, My Fortran programs which read from
>>  and write to file don't do this properly unless I include the FULL pathname
>>  (they used to write to the directory from which the program was started
>>  by default). Also, the Unix "./{file}" local file specifier won't work
>>  - I have to open a file, e.g. using
    
>>            open(1,file='/usr/users/joe_blow/myfile.dat',status='unknown')
    
I have no record of this being reported...  kinda hard to believe it doesn't
work.  The simplest test works for me:  this is x.f

        character a*40
        open (unit=1, file='./x.f')
 10     read (1,1000,end=999) a
 1000   format (A40)
        write (6,*) a
        go to 10
 999    end

This is with the V4.1 compiler and DFARTL374 on DUNIX V3.2 214.

We need more info... like what versions of everything and a sample program and
files that fail.

/Stan