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See line breaks and carriage returns in editor

Is there a text editor on Linux that allows me to see line breaks and carriage returns? Does Vim support this feature?

NOTE: sometimes newline ($) and carriage return (^M) are hidden in MANY color schemes, and also while using putty to ssh.
OP I think you should reconsider the selected answer. as the selected answer doesn't work. but CaptSaltyJack answer works well.
OP What will show BOTH is @arno 's solution. I needed to see BOTH, because I have a file randomly using all 3 fileformats... And arno 's solution works

Z
Zoe stands with Ukraine

To disagree with the official answer:

:set list will not show ^M characters (CRs). Supplying the -b option to vi/Vim will work. Or, once Vim is loaded, type :e ++ff=unix.


It's the Syntax. :help edit shows e[dit]! [++opt] [+cmd]. And :help ++e says The [++opt] argument can be used to force the value of 'fileformat' [..].
just to clarify, :set list shows newline ($), :e ++ff=unix shows CR (^M); if you want to see both, :set list then :e ++ff=unix
To expand on @dennis's comment, :set ff=unix tells Vim to change the line endings to unix style (as part of setting the fileformat), so the ^M characters are no longer there (and so are not displayed). :e ++ff=unix tells it to force-set the fileformat as unix without actually changing the contents. So vim reads it like a Unix file, sees the CR characters as extra and displays them as ^M.
Neither still doesn't work for me in vim for some reason... I mean neither -b option, nor :e ++ff=unix when inside :(
all right, :e ++ff=unix worked. Now how do I turn it off?
S
Shyam Habarakada

Assuming your vim settings for :set listchars=... is set to visualize the characters you are attempting to see, in this case the carriage return characters (typed with CTL + V, CTRM + M) —— otherwise, as reported in many of the comments on this answer, the ^M character will not show on :set list

:set list in Vim will show whitespace. End of lines show as '$' and carriage returns usually show as '^M'.


Same question here: superuser.com/questions/97692/…
Incorrect, :set list will NOT show ^M characters (CRs). Supplying the -b option to vi/vim will work. Or, once vim is loaded, type: :e ++ff=unix
FYI, to turn off the "set list" mode, use :set nolist
WRONG answer. :set list will NOT show ^M characters (CRs). Use -b option to vi/vim will work.
As I understand it, Vim will show the ^M characters only if it thinks the fileformat of the file is unix. This usually happens when one or more lines ends with the \n unix-style line break character, but the others end with \r\n CRLF combination that Windows uses. Then the lines with the CRLF line ending will show the ^M character.
P
Peter Mortensen

vi shows newlines (LF character, code x0A) by showing the subsequent text on the next line.

Use the -b switch for binary mode. For example , vi -b filename or vim -b filename --.

It will then show CR characters (x0D), which are not normally used in Unix style files, as the characters ^M.


I typically dont need to see the line ending, because I mostly work in Unix environment. But I would like to be warned about Windows type line endings if there is any in the file. Will vi -b filename or :set binary just show ^M if it is a windows type file and no other line endings otherwise?
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Paul van Leeuwen

Just to clarify why :set list won't show CR's as ^M without e ++ff=unix and why :set list has nothing to do with ^M's.

Internally when Vim reads a file into its buffer, it replaces all line-ending characters with its own representation (let's call it $'s). To determine what characters should be removed, it firstly detects in what format line endings are stored in a file. If there are only CRLF '\r\n' or only CR '\r' or only LF '\n' line-ending characters, then the 'fileformat' is set to dos, mac and unix respectively.

When list option is set, Vim displays $ character when the line break occurred no matter what fileformat option has been detected. It uses its own internal representation of line-breaks and that's what it displays.

Now when you write buffer to the disc, Vim inserts line-ending characters according to what fileformat options has been detected, essentially converting all those internal $'s with appropriate characters. If the fileformat happened to be unix then it will simply write \n in place of its internal line-break.

The trick is to force Vim to read a dos encoded file as unix one. The net effect is that it will remove all \n's leaving \r's untouched and display them as ^M's in your buffer. Setting :set list will additionally show internal line-endings as $. After all, you see ^M$ in place of dos encoded line-breaks.

Also notice that :set list has nothing to do with showing ^M's. You can check it by yourself (make sure you have disabled list option first) by inserting single CR using CTRL-V followed by Enter in insert mode. After writing buffer to disc and opening it again you will see ^M despite list option being set to 0.

You can find more about file formats on http://vim.wikia.com/wiki/File_format or by typing:help 'fileformat' in Vim.


P
Peter Mortensen

Try the following command.

:set binary

In Vim, this should do the same thing as using the "-b" command line option. If you put this in your startup (i.e., .vimrc) file, it will always be in place for you.

On many *nix systems, there is a "dos2unix" or "unix2dos" command that can process the file and correct any suspected line ending issues. If there aren't any problems with the line endings, the files will not be changed.


Unfortunately in my system (Ubuntu 16.04) set binary is not the same as vim -b filename.py. Any idea why? I did check the help and it does seem that what you say is generally correct. How do I figure out why this is so?
:e ++ff=unix does show the ^M correctly and doesn't show it when I use unix type files.. So I guess the problem is solved for now...
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Peter Mortensen

I suggest you to edit your .vimrc file, for running a list of commands.

Edit your .vimrc file, like this:

cat >> ~/.vimrc <<EOF
set ffs=unix
set encoding=utf-8
set fileencoding=utf-8
set listchars=eol:¶
set list
EOF

When you're executing Vim, the commands in file .vimrc are executed, and you can see this example:

My line with CRLF eol here ^M¶

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Peter Mortensen

By using cat and -A you can see new lines as $ and tabs as ^I:

cat -A myfile

'cat -A' is not as portable as 'cat -e'. -A is supported by GNU coreutils version of cat(1), but not other implementations (e.g., bsd, macos, etc.).
And :%!cat -A to use in vim (although that changes the contents of the buffer of course)
d
danilo

You can view break lines using the gedit editor.

First, if you don't have it installed, for Debian/Ubuntu/Mint based distros:

sudo apt-get install gedit

For Fedora/CentOS/RedHat based distros:

sudo dnf install gedit

or

sudo yum install gedit

Now, install gedit plugins:

sudo apt-get install gedit-plugins

or

Under Gnome2, user plugins were put into ~/.gnome2/gedit/plugins/
For Gnome3: ~/.local/share/gedit/plugins/

Download the plugins from: https://help.gnome.org/users/gedit/stable/gedit-plugin-guide.html.en#gedit-additional-plugins

and select Draw Spaces plugin, enter on Preferences, and chose Draw new lines:

https://i.stack.imgur.com/2CbdF.png

https://i.stack.imgur.com/W9S74.png

Using Visual Studio Code, you can install the Line endings extension.

Sublime Text 3 has a plugin called RawLineEdit that will display line endings and allow the insertion of arbitrary line-ending type

Shift + Ctrl + P and start type the name of the plugin, and toggle to show line endings.


apt-get will not work on all Linux systems (this question's scope). Perhaps state the assumptions? Ubuntu? Linux Mint? Ubuntu MATE? Debian?
@PeterMortensen, I added steps for CentOS,RedHad,Fedora (for Gnome desktop environments)