4.3 Configure script

The configure script produces a Makefile. It is controlled by environment variables (see below). It tries to use reasonable default values if they are not set (properly). In the script the machine type is determined with `uname -m`. According to the control variables and the machine architecture the compiler name and its compiler flags are composed. These are written into the header of a Makefile which is produced in the end. An existing Makefile is appended to

  Makefile_old.

Additionally, the compilation command is written into the file

  'compiler_flags.info'

in a form ready to be included in a Fortran program.