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Re: diff issue

Andrey Repin wrote:
>>>> When I'm comparing them with my usual macro
>>>> diff -bdu -x "CVS" -x ".svn" -I "\$Id.*\$" -I "\$Revision.*\$" -I
>>>> "\$Date.*\$" -I "\$Author.*\$" --strip-trailing-cr -- '1/backup.bat'
>>>> 'backup.bat'
>>>> It telling me that $Id$ lines are differ.
>>>> But when I remove the "@echo off" from second file, it telling me
>>>> that files are "identical" (the expected result).

Did you get something similar to the following ?

--- 1/backup.bat     2010-10-01 09:55:59.070190500 +0200
+++ backup.bat     2010-10-01 09:56:19.112194500 +0200
@@ -1,2 +1,3 @@
-rem $Id: backup.bat,v 1.1 2007/07/17 01:53:30 Daemon Exp $
+@echo off
+rem $Id: backup.bat 10 2010-09-30 01:22:14Z anrdaemon $
 rar a -ag-YYYY-MM-DD_HH-MM -- MinerTimer @MinerTimer.list

I suspect that the -I switch told diff "do not start a difference if
the line matches" rather than "consider this line to always match".

So diff found the differing "@echo" line, and went into "it's a diff"
mode until the identical "rar" line was found. So the "$Id" line is
included in the diff even though it matches the -I switch.

This behavio(u)r is counter-intuitive, but is probably required;
otherwise the generated diff would be unusable for patch(1).

On Fri, Oct 1, 2010 at 4:20 AM, Brian Wilson  wrote:
> I'm not sure what the "--" argument is used for (before the file names) though.

It's a convenient way to ensure that the command works with filenames
beginning with a dash.

GCS a+ e++ d- C++ ULS$ L+$ !E- W++ P+++$ L w++$ tv+ b++ DI D++ 5++
Life is complex, with real and imaginary parts.
"Ok, it boots. Which means it must be bug-free and perfect. " -- Linus Torvalds
"People disagree with me. I just ignore them." -- Linus Torvalds

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