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(g77-295.info)INCLUDE

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Including Source Text
---------------------

   Additional source text may be included in the processing of the
source file via the `INCLUDE' directive:

     INCLUDE FILENAME

The source text to be included is identified by FILENAME, which is a
literal GNU Fortran character constant.  The meaning and interpretation
of FILENAME depends on the implementation, but typically is a filename.

   (`g77' treats it as a filename that it searches for in the current
directory and/or directories specified via the `-I' command-line
option.)

   The effect of the `INCLUDE' directive is as if the included text
directly replaced the directive in the source file prior to
interpretation of the program.  Included text may itself use `INCLUDE'.
The depth of nested `INCLUDE' references depends on the implementation,
but typically is a positive integer.

   This virtual replacement treats the statements and `INCLUDE'
directives in the included text as syntactically distinct from those in
the including text.

   Therefore, the first non-comment line of the included text must not
be a continuation line.  The included text must therefore have, after
the non-comment lines, either an initial line (statement), an `INCLUDE'
directive, or nothing (the end of the included text).

   Similarly, the including text may end the `INCLUDE' directive with a
semicolon or the end of the line, but it cannot follow an `INCLUDE'
directive at the end of its line with a continuation line.  Thus, the
last statement in an included text may not be continued.

   Any statements between two `INCLUDE' directives on the same line are
treated as if they appeared in between the respective included texts.
For example:

     INCLUDE 'A'; PRINT *, 'B'; INCLUDE 'C'; END PROGRAM

If the text included by `INCLUDE 'A'' constitutes a `PRINT *, 'A''
statement and the text included by `INCLUDE 'C'' constitutes a `PRINT
*, 'C'' statement, then the output of the above sample program would be

     A
     B
     C

(with suitable allowances for how an implementation defines its
handling of output).

   Included text must not include itself directly or indirectly,
regardless of whether the FILENAME used to reference the text is the
same.

   Note that `INCLUDE' is *not* a statement.  As such, it is neither a
non-executable or executable statement.  However, if the text it
includes constitutes one or more executable statements, then the
placement of `INCLUDE' is subject to effectively the same restrictions
as those on executable statements.

   An `INCLUDE' directive may be continued across multiple lines as if
it were a statement.  This permits long names to be used for FILENAME.