FIX: F6422 on Unformatted File Opened with ACCESS='APPEND'

The information in this article applies to:

• Microsoft FORTRAN PowerStation for MS-DOS, version 1.0

SYMPTOMS

Attempting to CLOSE, REWIND, or BACKSPACE an unformatted file that was opened with ACCESS='APPEND' produces the run-time error:

   run-time error F6422:
   - no space left on device

RESOLUTION

Do not open unformatted files with ACCESS='APPEND'. Read to the end of the unformatted file and then start writing the new information. Another solution is to use FORM='BINARY' with ACCESS= 'APPEND'.

STATUS

Microsoft has confirmed this to be a problem in FORTRAN PowerStation version 1.0 for MS-DOS. This problem has been resolved with FORTRAN PowerStation maintenance release version 1.0a for MS-DOS.

FORTRAN PowerStation version 1.0 can be differentiated from the maintenance release version 1.0a by invoking the linker. Typing "link32 | more" from \F32\BIN directory will show version 2.8 for FORTRAN PowerStation version 1.0, and it will show version 1.0f for the maintenance release version 1.0a.

MORE INFORMATION

The following sample produces the F6422 error with Fortran PowerStation for MS-DOS version 1.0, but does not with version 1.0a.

Sample Code #1

Compile options: None

      open (1,file='newfile.dat',form='unformatted')
      do j=1,2
         write(1) j
      enddo
      close(1)
      open (1,file='newfile.dat',form='unformatted',access='append')
      do j=1,2
         write(1) j
      enddo
      close(1)  ! F6422 here
      end

Sample Code #2

Compile options: None

      open (1,file='newfile.dat',form='unformatted')
      do j=1,2
         write(1) j
      enddo
      close(1)
      open (1,file='newfile.dat',form='unformatted')
      do while (.not.EOF(1))
         read(1) j           ! READ to end of file
      enddo
      do j=1,2
         write(1) j          ! APPEND additional information
      enddo
      close(1)
      end