How to draw a flowchart from fortran 77 code.

Obtain the Fortran 77 Flowcharting Utility.

Generate a .dot file

./f77_diagram -l -o example.f

Install or get your sysadmin to install the package GraphViz, which contains lots of useful utilities.

Use the package dot to convert the .dot file which contains the information to draw a flowchart to a graphics format (here postscript).

dot -Tps -o

You now have a postscript file which you can view in your favourite ps file viewer.