Fortran

ITS has imported some Fortran software. To facilitate this, there is a copy of the old Fortran-40 compiler from DEC. It runs on top of an emulator for TOPS-10 system calls called DECUUO. The Fortran compiler is run by typing :dec sys:f40

HELLO; HELLO FOR is a sample "hello world" Fortran program. It can be compiled like this:

*:cwd hello
*:dec sys:f40
*hello=hello.for
^Z
^[^X.

This will produce a relocatable file HELLO REL. Note how F40 is using a TOPS-10 file name HELLO.FOR in the input. This is translated by DECUUO to an ITS file name HELLO FOR.

Next, the file must be linked. To do this, we invoke another DEC program called LOADER. When LOADER is done, it will leave the linked program in memory as the current job. Because it's a TOPS-10 program, we end with a twist: the magic 45$g command invokes DECUUO to massage the program for running on ITS.

*:dec sys:loader
hello/g
*45^[gd
*:pdump ts hello

:pdump is the DDT command to write an executable file. The TS HELLO file is now ready to run.