crlf to \n

rgb96 has asked for the wisdom of the Perl Monks concerning the following question:

Hey Monks,

I'm taking a file that was written in notepad, importing it to my linux machine, and trying to chomp the lines and display them in a tree view. As I quickly found out, chomp won't work with it's default value because windows format uses crlf and not \n. Quick question, is it best to just change the value of $/ ? And if so, is this the way i would do it?

local $/ = "\r\n";
open(FILE, "environments.txt);
my @temp = <FILE>;
foreach my $line (@temp){
chomp($line);
print $line;
}
[download]

print used instead of treeview just for illustration

Comment on crlf to \n Download Code

Replies are listed 'Best First'.
Re: crlf to \n by moritz (Cardinal) on Apr 02, 2009 at 14:36 UTC
`open my $file, '<:crlf', 'environments.txt' or die $!; while (@temp) { chomp; print; }` [download] The crlf IO layer converts crlf into \n while reading.	[reply] [d/l]
Re^2: crlf to \n by rgb96 (Acolyte) on Apr 02, 2009 at 14:51 UTC
Thanks guys, those will work.	[reply]
Re: crlf to \n by planetscape (Chancellor) on Apr 02, 2009 at 15:21 UTC
Use dos2unix, flip or flip: Newline conversion between Unix, Macintosh and MS-DOS ASCII files to convert. Or see Super Search: newline regex. HTH, planetscape	[reply]
Re: crlf to \n by kennethk (Abbot) on Apr 02, 2009 at 14:41 UTC
I transfer files between OS's on fairly regular basis. My solution is to just run the following one-liner as part of the transfer procedure - that way it doesn't matter what I feed it into on the far end. `perl -pi -e 's/\r\n/\n/;' filename` Information on the command-line switches above is found in perlrun.	[reply] [d/l]
Re^2: crlf to \n by codeacrobat (Chaplain) on Apr 02, 2009 at 23:10 UTC
or just: `perl -pi -e 'tr[\r][]d' environments.txt` [download] `print+qq(\L@{[ref\&@]}@{['@'x7^'!#2/"!4']});`	[reply] [d/l] [select]
Re: crlf to \n by dwm042 (Priest) on Apr 02, 2009 at 18:26 UTC
Since it hasn't been mentioned, and for completeness (planetscape's methods would be my recommendation for automated solutions): `1. load file into vi 2. in command mode: %s/^V^M//g (^V is literal mode, then add carriage return, or ^M) 3. save file.` [download] This might work with vim if you use vi compatibility mode; `vim -C` iirc. Otherwise vim tends to ignore eol differences. Update: Windows is not absolutely bound to crlf eols either. Load a Unix file into wordpad sometime. That's the classic unix eol test in Win32: looks funny in notepad, looks fine in wordpad.	[reply] [d/l]
Re^2: crlf to \n by zwon (Abbot) on Apr 02, 2009 at 19:09 UTC
In vim you can use 'set ff=dos' or 'set ff=unix' to save file with desired line-endings. So you can load file into vim, type :set ff=unix, and save file.	[reply]
Re^3: crlf to \n by Intrepid (Curate) on Apr 03, 2009 at 03:41 UTC
It's possibly worth noting that merely changing the ~~filetype~~ fileformat (`ff`) in Vim won't repair a file which has a mix of *nix and dos line-endings, and because of the still massive userbase of a few specific Microsoft tools (that are brain-dead on this score), such files are rather commonly encountered. In such a case one has to actively do something, and if one wants to do something inside Vim, it ought to work to do what dwm042 wrote in reply above. Soren Andersen / “somian” / “perlspinr”	[reply]