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I need to use the less command with the syntax highlighting of the vim command for python, C, bash and other languages.

How do I apply syntax highlighting colors according to vim colors for less command?

Gilles
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PersianGulf
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5 Answers5

63

Syntax highlighting of less, works just fine on most *nix systems. 

apt install source-highlight
export LESSOPEN="| /usr/share/source-highlight/src-hilite-lesspipe.sh %s"
export LESS=' -R '

On Fedora/RedHat based distros use /usr/bin/src-hilite-lesspipe.sh instead.

Even on Cygwin you can do it with the minor adjustment of the shell script path and installing with apt-cyg instead of apt.

However, using this drastically slows down browsing of large files. I suggest to use alias in such a way to only implement the LESSOPEN export above when needed, like this:

alias lessh='LESSOPEN="| /usr/bin/src-hilite-lesspipe.sh %s" less -M '

where the -M flag is convenient to also show filename and line number.

Also remember to copy the script into your bin path: 

cp /usr/share/source-highlight/src-hilite-lesspipe.sh /usr/bin/src-hilite-lesspipe.sh

UPDATE: 2019-07-24

Apparently, on more recent Cygwin installs, you have the following files in your path: 

source-highlight.exe
source-highlight-esc.sh
source-highlight-settings.exe

So now you also need to execute the source-highlight-settings.exe that will add the configuration file:
$HOME/.source-highlight/source-highlight.conf.

not2qubit
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    The alias 'lessh' doesn't work for me. Running bash on osx. Sigh. – SMBiggs Oct 17 '14 at 17:09
  • That is an entirely different issue, most likely due to OSX using different shell and environment options, which may affect the interpretation of single and double quotes, differently. You can check and set these with [`shopt -p`](http://wiki.bash-hackers.org/commands/builtin/shopt) and [`set`](http://wiki.bash-hackers.org/commands/builtin/set). – not2qubit Mar 20 '15 at 00:24
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    This worked for me on OSX: first I installed with: `brew install source-highlight`, then I added an alias: `alias lessh='LESSOPEN="| src-hilite-lesspipe.sh %s" less -R '` – mhvelplund Aug 23 '18 at 12:35
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less doesn't support syntax highlighting.

vim, like all vi clones has a read-only mode called view which you can use to just view files. it supports all features of vim including syntax highlighting.

e.g.

view filename.py

the main difference between view and vi is that view doesn't "lock" the file you're viewing by creating a .swp file.

cas
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  • if your `view command` means from `radare package` , it's not read only – PersianGulf Sep 17 '13 at 06:58
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    Hmm, my `view` command doesn't seem to support syntax highlighting. I've tried `:syntax enable` and `:syntax on`, but I always get `syntax: Not an editor command`. My `vim` supports highlighting, though. – Felix Sep 17 '13 at 10:14
  • @felix - do you have another `vi` like `nvi` or `elvis` installed? check your `/usr/bin/view` - on my debian system, it's a symlink to `/etc/alternatives/view` which is, in turn, a symlink to `/usr/bin/vim.basic`. – cas Sep 17 '13 at 10:29
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    Hmm, in my case it's a symlink to `/usr/bin/ex`, which, curiously, is owned by the `vi` package. – Felix Sep 17 '13 at 10:35
  • ah, but which `vi` package? vim? elvis? nvi? – cas Sep 17 '13 at 11:28
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    I can confirm what @Felix says, on `arch linux` `view` is a symlink to `/usr/bin/ex` of `core/vi` package. – x-yuri May 16 '15 at 16:51
  • See [this answer](http://superuser.com/a/244029/185665): `alias vless='vim -u $VIMRUNTIME/macros/less.vim'` – x-yuri May 16 '15 at 20:32
  • To use highlighting in a pipe, like `grep something somewhere | less` use this on vi: `grep something somewhere | view -` – Michael Nov 15 '18 at 15:56
  • Erm, `less` **does** support syntax highlighting on 3 out of 3 of my systems... – AstroFloyd May 24 '20 at 08:24
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I tend to disagree with Ingo, less can be taught to highlight syntax. Check out this answer on SuperUser. Basically, you have to install GNU's source-highlight (available in all major distro package repos), and then add the following to your .bashrc (or .bash_profile or what have you):

export LESSOPEN="| /path/to/src-hilite-lesspipe.sh %s"
export LESS=" -R "

However, note that source-highlight is not as powerful as vim's highlighter. Use whatever suits you best.

Community
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Felix
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less requires third-party tools to highlight syntax elements, but Vim can be used as a pager, i.e. a replacement for less. There are more advanced plugins, but the basic script actually ships with Vim ($VIMRUNTIME/macros/less.sh). For the full information, see Using vim as a syntax-highlighting pager on the Vim Tips Wiki.

If you're already using Vim, the consistency (and support of almost any file type) makes this worth a try.

Ingo Karkat
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    I'm surprised people doesn't even bother to Google before posting wrong answers... – not2qubit Jun 29 '14 at 11:48
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    @user1147688: If you carefully read Felix's answer, the GNU source-highlight is an external program, and the integration with less is very loose. It's not `less` that does the highlighting; but Vim indeed has this capability built-in. – Ingo Karkat Jun 29 '14 at 11:59
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    For the question "How do I apply syntax highlighting colors according to vim colors for less command?", the answer "By using source-highlight" seems like a more correct answer that "By using vim". – Zano Mar 10 '15 at 09:21
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    +1 but I'm sure what these comments are trying to say -- can't tell if they're even positive or negative ("...google before posting wrong answers"?, "installing xyz is more correct than just using vim"?). This answer is clearly the "most correct answer". Basically the OP didn't know this feature of vim existed, and this answer lets the OP know that it exists. Occam's razor ftw. The answer could only be improved by showing an example, e.g., `$ diff file1.c file2.c | /usr/share/vim/vim74/macros/less.sh` – michael Dec 05 '16 at 02:51
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After dabbling in some of the answers above, I think the most configuration-free solution is to just install and use vimpager.

It is available on github, homebrew, Arch (older version), AUR (latest), and maybe more.

After install you should be able to immediately use vimpager instead of less at your shell.

To utilise vimpager in other instances where less is used, you can change the PAGER variables your shell config (.bashrc etc.) by adding:

export PAGER=/usr/local/bin/vimpager
export MANPAGER=/usr/local/bin/vimpager

The install paths may (need to?) be different on OSX, but this works fine on Arch linux.

You can then set an alias to always substitute less for vimpager, in the same file:

alias less=$PAGER

(As described at the github readme)

steve_b
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