
- language requirements: Fortran 2003, C99

- no tabs in C- and Fortran-source code (untabify)

- no trailing whitespace (whitespace-cleanup)

- It is okay (but not required) to declare a variable in the control part of
  a 'for' loop (C99 feature): "for(int i=0; i<n; i=++) {...}". Please do not
  add noise to commits for the sole purpose of having a c89 look.

- In C parts of the code, identifiers should be mixed case to conform
  with reserved name policy. Implementors reserve identifiers with all
  lower-case (plus digits and underscore) also identifiers starting
  with an underscore are reserved.

