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Writing to $STDLIST

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E0300 Edition 6 ♥
E0692 Edition 5

You can write data from your program to your program's standard list device $STDLIST using two intrinsics:

  • PRINT

  • FWRITE

Normally, $STDLIST for jobs is a line printer and for sessions a terminal. You can write a string of ASCII characters from an array in your program to $STDLIST with the PRINT intrinsic. You do not need to use HPFOPEN/FOPEN to open the standard list device in order to use PRINT.

NOTE: The PRINT intrinsic is limited in its usefulness in that FILE commands are not allowed. In addition, you cannot use the FCHECK intrinsic to determine error conditions encountered by PRINT. You may find it more convenient (and a better programming practice) to use the HPFOPEN/FOPEN intrinsic to open the file $STDLIST, then write to this file using FWRITE.

You can also use the FWRITE intrinsic to write data from your program to the standard list device $STDLIST, if you opened $STDLIST with HPFOPEN/FOPEN. In this case, the HPFOPEN/FOPEN call returns a file number that identifies $STDLIST. You would then write to $STDLIST sequentially using FWRITE. For more information about opening $STDLIST, refer to chapter 5, "Opening a File".

Example 8-3 is an HP Pascal/iX code segment that contains a PRINT intrinsic call that transmits a message to $STDLIST.

Example 8-3. Writing to $STDLIST Using PRINT 

             .
             .
             .
  var
     message        : packed array [1..72] of char;
     message_length : shortint;                 {declare PRINT parms}
     controlcode    : 0..65535;
             .
             .
             .
     message        := 
       'WRITING A MESSAGE TO THE STANDARD LIST DEVICE.';
     message_length := -46              {message is 46 bytes long   }
     control_code   := 0;
     PRINT ( message,                   {message written to $STDLIST}
             message_length,            {number of bytes in message }
             controlcode                {set to default             }
           );
             .
             .
             .
For more information about PRINT parameters, refer to the MPE/iX Intrinsics Reference Manual. In appendix A, "HP Pascal Program Examples, "example A-2 uses the PRINT intrinsic to write messages to $STDLIST.



Sequential Access and Random Access

Writing Messages to the System Console