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File permission _feature_



Sergey, et. al.

I believe I have found a case where the gnu-win32 file permission
behavior and modification date update behavior differs from the
reference platform (i.e. Linux and SunOS in my case).  I have
observed this _feature_ while testing a bash shell function I wrote
to strip those pesky <CR> characters from my text files.

Please see the following bash session:



ryl@JERRY:
ryl@JERRY: date
Wed Nov 19 17:38:38 GMT-8:00 1997
ryl@JERRY: umask
077
ryl@JERRY: ll Eq_lease.txt
-rw-------   1 0        everyone    15355 Jan 25  1996 Eq_lease.txt
ryl@JERRY: cp Eq_lease.txt Eq_lease.cpy
ryl@JERRY: ll Eq_lease.*
-rw-------   1 0        everyone    15355 Nov 19 17:39 Eq_lease.cpy
-rw-------   1 0        everyone    15355 Jan 25  1996 Eq_lease.txt
ryl@JERRY:
ryl@JERRY: type strip
strip is a function
strip ()
{
    tmp_file="/tmp/`date +%j%H%M%S`";
    for f in $*;
    do
        cp $f $tmp_file;
        tr -d '\15' <$tmp_file >./$f;
        rm $tmp_file;
    done
}
ryl@JERRY: chmod 644 Eq_lease.cpy
ryl@JERRY: ll Eq_lease.*
-rw-r--r--   1 0        everyone    15355 Nov 19 17:44 Eq_lease.cpy
-rw-------   1 0        everyone    15355 Jan 25  1996 Eq_lease.txt

** Feature 1 **

	Use of the "chmod" command as above should not modify the
	file modification date/time stamp.

	In the Unix world, a change of the file permission writes on the
	i-node, not the file, hence the file content remains unaltered.


ryl@JERRY:
ryl@JERRY: strip Eq_lease.cpy
ryl@JERRY: ll Eq_lease.*
-rw-------   1 0        everyone    15030 Nov 19 17:47 Eq_lease.cpy
-rw-------   1 0        everyone    15355 Jan 25  1996 Eq_lease.txt
ryl@JERRY

** Feature 2 **

	I would expect using 'tr' as above to cause bash to dup()
	stdout and call freopen() on the existing file "Eq_Lease.cpy"
	thus keeping the permission word unchanged.

	I am using Sergey's cygwin32.dll and bash:

		ryl@JERRY: bash --version
		GNU bash, version 2.01.0(4)-release (i386-pc-cygwin32)
		Copyright 1996 Free Software Foundation, Inc.
		ryl@JERRY: ident cygwin.dll
		cygwin.dll:
			 $Id: regexp.c,v 1.5 1995/06/07 03:55:49 cgd Exp $
			 $Id: regerror.c,v 1.3 1993/08/26 00:45:33 jtc Exp $
			 $Id: regsub.c,v 1.4 1995/06/05 19:42:35 pk Exp $
		ryl@JERRY:

I confess to not having downloaded the sources and looked for this.

I don't feel this a real serious problem, when you play in a 
cathouse (WinNT), you should expect things to be a bit messy.
This may well be a side effect of something goofy NT does.  I
am just beginning to learn NT, so it would take me a while to
get to the bottom of this.  It would be nice to see it fixed.

I do sincerely appreciate the efforts of those who work on
gnu-win32 and cygwin32 as it is helping me by easing my pain
as I learn NT.

Thanks for listening.  I apologize if this has been dealt with,
I'm rather new to this environment.

Regards,
Ray

PS: BTW, why is $Id$ not being compiled into all modules in
	"cygwin32.dll"?  Please don't tell me this code is not
	being controlled with CVS. ;-)

--
"We must respect the other fellow's religion, but only in
 the sense and to the extent that we respect his theory
 that his wife is beautiful and his children smart."
		 [H.L. Mencken, Minority Report, 1956]
--
Raymond Y. Lillard                    Innovix Technologies, Inc.
ray.lillard@innovix.com               Suite 200
v:415-366-6964                        643 Bair Island Rd. 
http://www.innovix.com                Redwood City, CA  USA






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