Dann Corbit wrote: ↑Sat May 30, 2020 9:43 am
I used to run a fortran iv compiler on IBM 360 and 370 hardware in the late 1970s.
You will need:
// exec fortfclg
for execute fortran (f) compile, link, go
I don't remember if the F is for fortran (f)our or if it was the (F) version of the compiler.
Very close. FORTGCLG as it turns out. I actually found Fortran IV G for MVS which contrary to rumors is actually in the public domain. I now have it installed on MVS 3.8 using TK4- via Hercules emulator, and a version of the partially cleaned-up Blitz code loaded in a PDS. Apart from the necessity of upper case for FORTRAN, it seems to be friendly to Blitz6 code generally. Easy mode at last, perhaps.
For mainframe nostalgia, TK4- is a turnkey setup. You can run it under Linux or Cygwin. The opensource SPF environment and period everything-else takes some getting used to, especially if your job is using modern z/OS.
For PC platforms, the last version of gcc that featured g77 was 3.4. That would get one to the -ff66 switch and "easy mode".
Talk about a blast from the past! It's "Back To The Future!"
Taking ideas is not a vice, it is a virtue. We have another word for this. It is called learning.
But sharing ideas is an even greater virtue. We have another word for this. It is called teaching.
Taking ideas is not a vice, it is a virtue. We have another word for this. It is called learning.
But sharing ideas is an even greater virtue. We have another word for this. It is called teaching.
One thing that may be helpful is to give:
//class=P, time=1440
because on an IBM mainframe, a job with more than 200K RAM requires special permission (class =p means high priority) and time=1440 means let the job run as long as it takes, because the job gets a forced timeout when the time limit is exceeded.
Class=D is good for up to 200K. Class=A is only for tiny jobs.
Taking ideas is not a vice, it is a virtue. We have another word for this. It is called learning.
But sharing ideas is an even greater virtue. We have another word for this. It is called teaching.
A horrifying thing about FORTRAN IV is that only the first two letters in a variable name are recognized.
so:
JIVE =1
JIM = 2
both represent the same variable. The easiest way to keep track is simply to not use variable names longer than two letters.
Taking ideas is not a vice, it is a virtue. We have another word for this. It is called learning.
But sharing ideas is an even greater virtue. We have another word for this. It is called teaching.
Dann Corbit wrote: ↑Thu Jun 04, 2020 6:43 pm
A horrifying thing about FORTRAN IV is that only the first two letters in a variable name are recognized.
so:
JIVE =1
JIM = 2
both represent the same variable. The easiest way to keep track is simply to not use variable names longer than two letters.
Dann Corbit wrote: ↑Thu Jun 04, 2020 6:33 pm
One thing that may be helpful is to give:
//class=P, time=1440
because on an IBM mainframe, a job with more than 200K RAM requires special permission (class =p means high priority) and time=1440 means let the job run as long as it takes, because the job gets a forced timeout when the time limit is exceeded.
Class=D is good for up to 200K. Class=A is only for tiny jobs.
Good to know. This seems to be the CLASS convention for MVS3.8j. These days, class designation is determined by site engineers. At my shop, user short jobs are CLASS=L, longish ones CLASS=M and infinite jobs and TAPE are CLASS=H, and "production jobs" (run by the production job scheduler) are CLASS=P.
But when BLITZ6 is finally built, I imagine it should run under TSO for interactivity.
TSO was in beta when I worked on the IBM mainframe.
At the time, we saw one line of input at the terminal.
It was like DOS edlin from way back in the day.
At the time, I thought it was utterly incredible.
"Look at that! I am changing the virtual image of these cards right from this terminal!"
Taking ideas is not a vice, it is a virtue. We have another word for this. It is called learning.
But sharing ideas is an even greater virtue. We have another word for this. It is called teaching.
Thanks very much for that link. Turns out that Fortran of this vintage has no built-in capability for acquiring DATE/TOD information. No problem. The solution is to link into your project a callable assembler subroutine that uses a TIME macro that returns these values to your program. It works on my small test program.
The other required system hook for TSO interactivity is an "attention interrupt" handler, i.e. pressing the ATTN or PA1 key to signal BLITZ that the user wants to enter the opponents move while the program is pondering. BLITZ has a "break" subroutine designed to be invoked by this kind of interrupt. Once again the solution an assembler subroutine that invokes the STAX macro which adds a hook to your project for directing ATTN interrupts to a specified subroutine address (the "break" subroutine in BLITZ). Haven't coded this yet but once done, then compile AND link can commence.
Meanwhile all the Fortran modules now compile without errors with the FORTRAN IV G compiler. Two other compilers on this system, FORTRAN-H from the Goddard Space Flight Center and FORTRAN-H-EXTENDED, have optimization flags (unlike the G compiler). If the program gets to a smooth-running state under G, then optimization using one of the H compilers might be productive.
