I have a set of scripts to update files that have DOS-style line endings. I've written my scripts using a perl version built for Cygwin, and have been careful to use '\r\n' to terminate lines in my print statements. Someone else ran the same script using a perl version built for Windows, and he wound up with an extra carriage return.

How can I make my code work consistently across Perl versions?

The cygwin build is "perl, v5.10.0 built for cygwin-thread-multi-64int". With this version, the perl command

perl -e 'print "unix\n";print "dos\r\n";' | cat -e

produces the output

unix$
dos^M$

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where carriage returns are displayed as ^M and line feeds as $. The same code executed with the Windows build ("perl, v5.6.1 built for MSWin32-x86-multi-thread") produces output

unix^M$
dos^M^M$

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In case it's relevant, the more complete "perl -v" output is shown below, first for the newer Cygwin build and second for the older Windows build: 
> perl -v

This is perl, v5.10.0 built for cygwin-thread-multi-64int
(with 6 registered patches, see perl -V for more detail)

Copyright 1987-2007, Larry Wall

Perl may be copied only under the terms of either the Artistic License
+ or the
GNU General Public License, which may be found in the Perl 5 source ki
+t.

Complete documentation for Perl, including FAQ lists, should be found 
+on
this system using "man perl" or "perldoc perl".  If you have access to
+ the
Internet, point your browser at http://www.perl.org/, the Perl Home Pa
+ge.

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> Perl.exe -v

This is perl, v5.6.1 built for MSWin32-x86-multi-thread
(with 1 registered patch, see perl -V for more detail)

Copyright 1987-2001, Larry Wall

Binary build 629 provided by ActiveState Tool Corp. http://www.ActiveS
+tate.com
Built 12:27:04 Aug 20 2001


Perl may be copied only under the terms of either the Artistic License
+ or the
GNU General Public License, which may be found in the Perl 5 source ki
+t.

Complete documentation for Perl, including FAQ lists, should be found 
+on
this system using `man perl' or `perldoc perl'.  If you have access to
+ the
Internet, point your browser at http://www.perl.com/, the Perl Home Pa
+ge.

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In reply to Perl Windows vs Cygwin installs by gholley0

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