topic Re: Removing ^M from string in Operating System - Linux

Removing ^M from string

Henry Chua — Tue, 19 Dec 2006 21:17:46 GMT

Hi all,

I try this to remove "^M" from a string.. but does not seem to work.. anyone know why??
.....
my $var = "testing123^M";
$var = s/^V^M//;
print "var=$var";
....

Thanks
Henry

Re: Removing ^M from string

Patrick Wallek — Tue, 19 Dec 2006 21:27:30 GMT

If you have a whole file, use the dos2ux command.

# dos2ux file1 > file2

will remove all ^M sequences from file1 and save it in file2.

Re: Removing ^M from string

Henry Chua — Tue, 19 Dec 2006 21:34:11 GMT

Hi Patrick,

I'll like to implement this to control the string parse to a text so i am using perl to do this. Thanks.

Best regards
Henry

Re: Removing ^M from string

Hein van den Heuvel — Tue, 19 Dec 2006 23:04:53 GMT

Henry,

The ^M or 'CR = Carriage Return" is best represented in perl as \r
You could also use the octal code \012.

Compare this with the more common ^J or 'LF = LineFeed'
For that one you know to use \n or \015.

See: http://www.perl.com/doc/manual/html/pod/perlop.html

Look for 'interpolation'

And also check an ascii table. For example:
http://www.asciitable.com/

Hein.

Re: Removing ^M from string

Peter Nikitka — Wed, 20 Dec 2006 03:00:35 GMT

Hi,

if you run perl under windows, you may have to use 'binmode' before you use 'print'.

In your example, the syntax must be adjusted; I suggest:

...
($var1 = $var) =~ s/\r//;
print $var1;
...

mfG Peter

Re: Removing ^M from string

H.Merijn Brand (procura — Wed, 20 Dec 2006 03:05:21 GMT

As Hein said. CR is \r, not ^M
If you want to denote it in CTRL terms, perl offers you \cM, but that is unportable (think EBCDIC), as you now tell exactly which codepoint you use instead of using the correct escape

^V^M is a vi or shell notation. Ctrl-V tells both to take the next character literally. Perl doesn't know about that.

As \r (or \cM) is whitespace, it also falls in that category, and

(my $var = "testing123 \r") =~ s/\s+$//;

will now remove both the \r and the space

Note also that you 'print "var = $var";' will not print a newline unless you used the -l option on perl invocation. That should probably be 'print "var = $var\n";'

Enjoy, Have FUN! H.Merijn

Re: Removing ^M from string

PAVIC Thierry — Thu, 21 Dec 2006 04:07:33 GMT

try those 2 ways

cat | tr -d "^V^M" >

sed -e "s/^V^M//" >