INCLUDE          Process Code from External File               MASM Directive

  INCLUDE filename

    Causes the assembler to process source code from an external file.

       Notes:     Filename must refer to an existing file, or the
                  assembler will issue an error message and stop. A full
                  or partial path may be included in filename, with either
                  / or \ used as path separator characters. If you have
                  used the MASM /I switch to specify an "include file
                  path" at the command line, do not use that path in your
                  INCLUDE directive.  MASM first checks any path specified
                  with the MASM /I option.  Then if the file is not found,
                  MASM checks the current directory.  If the file is still
                  not found, then MASM will issue an error message and
                  stop.

                  When the assembler encounters an INCLUDE directive, it
                  reads and processes the specified file entirely before
                  returning to the file that issued the INCLUDE. INCLUDE
                  directives may be nested.

                  Code generated from INCLUDE files is marked with the
                  letter 'C' in MASM listings.