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How to use different colors in grep file?
Plus it uses different colors for different patterns. cat FILE | h ‘PAT1’ ‘PAT2’ You can also pipe the output of h to less -R for better reading. To grep and use 1 color for each pattern, cxpgrep could be a good fit. As grep -E ‘|pattern’ has already been suggested, just wanted to clarify it’s possible to highlight the whole line too.
Is there a shell script to colorize grep?
Here is a shell script that uses Awk’s gsub function to replace the text you’re searching for with the proper escape sequence to display it in bright red: Unfortunately, it doesn’t have all the functionality of grep. For more information , you can refer to an article ” So You Like Color ” in Linux Journal
What happens when there is no match in grep?
Most other grep variants support this too. However: 1) no output is produced when no match is found and 2) this option has a negative impact on grep’s efficiency: when the -C value is large this many lines may have to be temporarily stored in memory for grep to determine which lines of context to display when a match occurs.
Is there a color switch for grep on Solaris?
The grep solution is very clever, but the –color switch on grep is not available everywhere. For instance, I just tried this solution on a Solaris box running bash, and another running ksh, and my local Mac OS X machine running zsh. All worked just fine. Solaris choked on the grep –color solution, however.
How to grep while viewing the whole file?
To highlight patterns while viewing the whole file, h can do this. Plus it uses different colors for different patterns. cat FILE | h ‘PAT1’ ‘PAT2’ You can also pipe the output of h to less -R for better reading. To grep and use 1 color for each pattern, cxpgrep could be a good fit.
How do you print a line in grep?
In each line, you globally replace anything matching the given regular expression with itself ( &) wrapped in the ANSI escape sequences for desired color (which grep –color does for you). After processing all of the possible matches, you need to explicitly print the line.
How to substitute match with itself in grep?
You can use awk to substitute each match with itself wrapped in the correct control code. In each line, you globally replace anything matching the given regular expression with itself ( &) wrapped in the ANSI escape sequences for desired color (which grep –color does for you).
How to display line number while doing grep on a file?
There is the option -n, and many more in the manual page, worth reading. grep -n prefixes each line of output with the line number in the input file. Is this what you are looking for? This will color the match as well for easy reading. Have you checked cat -n ‘filename’. This will print the line numbers.
How to grep and highlight the whole file?
You can also pipe the output of h to less -R for better reading. To grep and use 1 color for each pattern, cxpgrep could be a good fit. As grep -E ‘|pattern’ has already been suggested, just wanted to clarify it’s possible to highlight the whole line too. For example tail -f /somelog | grep –color -E ‘| \\ [2\\].*’:
How to use egrep instead of grep in Bash?
Either escape it using \\ or tell grep that the search text has to be interpreted as regular expressions by adding -E or using the egrep command instead of grep. The search text “pattern|$” is actually a trick, it will match lines that have pattern OR lines that have an end.
Why does grep not print when redirected to a file?
Grep seems to not want to print them when you redirect it to a file, so you need to force it to: Now, when you print the file to the console it will be printed with the colors, because Bash interprets those characters as “use this color”. However, if you open it in an editor like vim, you’ll get some strange characters.
Is there a way to highlight a text in grep?
i.e. you can highlight the text that grep matches with color. This is controlled by “–color” option with grep command which basically surround the matching string with the marker find in GREP_COLOR environment variable. Grep’s default highlight color is red (shown below in the snap).