The Listing File

Every job will open one file which is intended to be read by a human. When using the ILL CCSL options this file is given the name of the main program and extension .lis. On a UNIX system there may be an extra line at the start of the program dialogue saying:
Existing file arrnge.lis will be overwritten OK? (Y/N) :
This will occur if arrnge has been run before in the same directory. It reminds the user that UNIX will overwrite the listing file from the previous run and that, if this is not what is wanted, he should exit from the program and save the listing with a different name. With the RAL options, the user will be asked to name the listing file, and if he responds by typing RETURN the file-name will default as above. So at RAL, there will be an extra line at the start of the dialogue saying :
Give name for Output

The listing file, which is on logical unit LPT, is opened by a call of OPNFIL, from SUBROUTINE INITIL, usually from the call of PREFIN which occurs near the start of most CCSL programs. If the user wishes to open a specific unit number, say 8, he must set LPT=8 before the CALL PREFIN .

If he does not do this OPNFIL (via NOPFIL) will choose its own unit number.