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From: Clive Page <use...@page2.eu>
Newsgroups: comp.lang.fortran
Subject: Re: Get Key Function?
Date: Sun, 3 May 2009 10:52:20 +0100
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In message <87zldw6ajc....@roark.xbeta.org>, Jason Blevins 
<jrble...@sdf.lonestar.org> writes
>it mentions reading single keystrokes.  Unfortunately, it says there
>isn't a portable way to do this in Fortran, but he offers a C function
>with some instructions on how to call it from Fortran:

>http://www.star.le.ac.uk/~cgp/sys_keyin.c

As noted earlier, this works on some Unix-like systems including Linux, 
but not on Windows.

>I would imagine there is a way to do this in Fortran 2003 using
>stream input from stdin, but I couldn't get anything working.
>Maybe someone else knows...
>
>If you don't mind using something non-standard, I know that
>GFortran has an FGET extension for this.  It's likely that
>G95 has a similar extension.
>
>http://gcc.gnu.org/onlinedocs/gcc-4.4.0/gfortran/FGET.html

I've tried this too, but can't get it to read single keystrokes - the 
keystroke read still needs a RETURN at the end.

On Windows the nearest I've been able to find uses a function in the 
GrWin library, which can be downloaded from:
http://spdg1.sci.shizuoka.ac.jp/grwinlib/english/

This contains a function kbgetch(n) which returns the integer code of 
the next single keystroke.  Normally n=0 but if n=1 then the character 
is echoed to stdout.

This can be linked using g95 or gfortran on Windows-XP using a command 
like this:
 >g95 testkbd.f90 -Wl,--subsystem,console -lGrWin -mwindows -lg2c

I have no idea what the switch "-Wl,--subsystem,console" is doing, it is 
just a bit of magic I found in the GrWin files.  If anyone understands 
it, please post.

It is, as you say, a pity that this cannot be done in a way that is 
portable across operating systems.

-- 
Clive Page