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(g77-300.info)g77stripcard

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g77stripcard
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   The `g77stripcard' program handles removing content beyond column 72
(adjustable via a command-line option), optionally warning about that
content being something other than trailing whitespace or Fortran
commentary.

   This program is needed because `lex.c' doesn't pay attention to
maximum line lengths at all, to make it easier to maintain, as well as
faster (for sources that don't depend on the maximum column length
vis-a-vis trailing non-blank non-commentary content).

   Just how this program will be run--whether automatically for old
source (perhaps as the default for `.f' files?)--is not yet determined.

   In the meantime, it might as well be implemented as a typical UNIX
pipe.

   It should accept a `-fline-length-N' option, with the default line
length set to 72.

   When the text it strips off the end of a line is not blank (not
spaces and tabs), it should insert an additional comment line
(beginning with `!', so it works for both fixed-form and free-form
files) containing the text, following the stripped line.  The inserted
comment should have a prefix of some kind, TBD, that distinguishes the
comment as representing stripped text.  Users could use that to `sed'
out such lines, if they wished--it seems silly to provide a
command-line option to delete information when it can be so easily
filtered out by another program.

   (This inserted comment should be designed to "fit in" well with
whatever the Fortran community is using these days for preprocessor,
translator, and other such products, like OpenMP.  What that's all
about, and how `g77' can elegantly fit its special comment conventions
into it all, is TBD as well.  We don't want to reinvent the wheel here,
but if there turn out to be too many conflicting conventions, we might
have to invent one that looks nothing like the others, but which offers
their host products a better infrastructure in which to fit and coexist
peacefully.)

   `g77stripcard' probably shouldn't do any tab expansion or other
fancy stuff.  People can use `expand' or other pre-filtering if they
like.  The idea here is to keep each stage quite simple, while providing
excellent performance for "normal" code.

   (Code with junk beyond column 73 is not really "normal", as it comes
from a card-punch heritage, and will be increasingly hard for
tomorrow's Fortran programmers to read.)