fppfpp is the preprocessor used by the NAG Fortran compiler. It optionally accepts two filenames as arguments: input-file and output-file are, respectively, the input file read and the output file written by the preprocessor. By default standard input and output are used.
When used via nagfor, either because the input source file type was
automatically recognised as requiring preprocessing (e.g. .ff90 files),
or the -fpp option was used, the macro
__NAG_COMPILER_RELEASE is automatically defined to be the integer
release number (major*10+minor, e.g. 61 for release 6.1), and the
macro __NAG_COMPILER_BUILD is automatically defined to be the build
number (for release 6.1 this will have a value greater than 6100).