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grep is one of the most commonly used command in linux. It feels to me that its basic feature to highlight the string you searched for on the output lines. this can be achieved by --color option.

Typing --color every single time is annoying and also not productive. Is there any way to change grep to behave as grep --color.

I tried writing a small script named it grepd and added this to my PATH variable. But the script doesnt work on the input grepd . Any suggestions please.

#!/bin/bash
grep --color $1 $2
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Simply add the following alias to your shell's configuration file, e.g. .bashrc or .bash_profile (depending on which you use, see here):

alias grep='grep --color=auto'

You can simply use it as grep.

There's usually no need to make scripts when simple command aliases do the same thing just fine. In fact your script wouldn't even work if you wanted to pass more options to grep. In case you need a tiny snippet that can deal with arguments, you should use functions.

  • 9
    Or equivalently, set the GREP_OPTIONS environment variable: export GREP_OPTIONS='--color=always' – Jérôme Mar 28 '17 at 21:41
  • This doesn't add the color option if you use fgrep or egrep, you would need seperate aliases for those. Also, @Jérôme: GREP_OPTIONS is marked as deprecated in the grep man page. – Thayne Jan 23 '18 at 5:23
  • @Thayne only for GNU grep and not others like FreeBSD grep. And as far as I can tell, it's been 4 years since that was changed and it's still supported. Depreciated does not mean removed. – cde Feb 2 '18 at 20:14
  • This is what I usually do, however it doesn't work right in some cases. For example: some_command | xargs grep foo will not be colorized because xargs doesn't use the alias. – TM. Apr 30 '18 at 20:17
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#!/bin/sh
exec grep --color "$@"

This illustrates the standard way of "wrapping" a command with a shell script, when the command doesn't quite work the way that you like.

The exec avoids creating an extra process (one for the script and one for grep). You could leave it out if you like.

The "$@" is replaced by all of the script's arguments, no matter how many there are. It correctly preserves arguments with spaces and other characters that are special to the shell.

  • The "exec grep" should be "exec /bin/grep" – Berend de Boer Jul 23 '15 at 6:50
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    @BerenddeBoer Not really. "exec grep" would work just fine. There's nothing wrong with searching the path for grep. – Kenster Jul 24 '15 at 1:47
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try putting export GREP_COLORS='AUTO' in your ~/.bashrc - for me it works.

from man grep

       --color[=WHEN], --colour[=WHEN]
          Surround  the  matched (non-empty) strings, matching lines, context lines, file names, line numbers, byte offsets, and separators (for fields and groups of context lines) with escape sequences
          to display them in color on the terminal.  The colors are defined by the environment variable GREP_COLORS.  The deprecated environment variable GREP_COLOR is still supported, but  its  setting
          does not have priority.  WHEN is never, always, or auto.
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    GREP_COLORS is the set the actual colours. Setting to AUTO should not show any colours. export GREP_OPTIONS='--color=auto' should be the answer. – user137369 Jan 19 '18 at 13:23

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