Help Files: Fortran77: Tapes

     HELP                      Sep. 15, 1984                 F77/TAPES



                  Using magnetic tapes with f77 programs

     Fortran logical units may be used for disk files,  but  not  gen-
     erally  for  reading  and  writing  magnetic tapes.  For magnetic
     tapes, use the special routines described in "man 3f  topen".   A
     sample  program  to  read  an  unblocked  tape  is  in  "help f77
     tp_ex1.f", a sample to read  a  blocked  tape  is  in  "help  f77
     tp_ex2.f".  It is set up to get the device name from the environ-
     ment variable 'tape1'.  The commands to run the program are  (as-
     suming the source is in prog.f):

             #       compile the program
             f77 prog.f
             #       mount tape, put device name in
             #       environment variable 'tape1'
             setenv tape1 `tape -mount -message -reel=99999`
             #       run the program if the tape was mounted ok.
             if( !$status ) a.out

     If you need to rerun the program, to rewind the tape, either  use
     the trewin() function (see "man 3f topen") or use:

             mt -t $tape1 rew

     or use the UNIX "rewind" command.