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How to print blank lines with grep-E?
Here, grep -e means the extended version of grep. ‘^$’ means that there isn’t any character between ^ (Start of line) and $ (end of line). ‘^’ and ‘$’ are regex characters. So the command grep -v will print all the lines that do not match this pattern (No characters between ^ and $). This way, empty blank lines are eliminated.
What does grep-E mean in grep Stack Overflow?
The three blank lines in the original output would be compressed or “squeezed” into one blank line. Here, grep -e means the extended version of grep. ‘^$’ means that there isn’t any character between ^ (Start of line) and $ (end of line). ‘^’ and ‘$’ are regex characters.
How to show same number of lines before and after in grep?
If you want the same number of lines before and after you can use -C num. This will show 3 lines before and 3 lines after. -A and -B will work, as will -C n (for n lines of context), or just -n (for n lines of context… as long as n is 1 to 9).
What’s the difference between a 5 and a 5 in grep?
-5 gets you 5 lines above and below the match ‘thestring’ is equivalent to -C 5 or -A 5 -B 5. Grep has an option called Context Line Control, you can use the –context in that, simply, If you search code often, AG the silver searcher is much more efficient (ie faster) than grep.
How to show lines before and after in grep?
If you want the same number of lines before and after you can use -C num. grep -C 3 foo README.txt This will show 3 lines before and 3 lines after.
How do you remove blank lines in egrep?
\\S means match non-blank characters. egrep already do regex, and the \\s is white space. The + duplicates current pattern. Here is another way of removing the white lines and lines starting with the # sign. I think this is quite useful to read configuration files.
How to delete comments and blank lines in Linux grep?
This allows us to use the pipe to represent the “or” condition in our pattern. The -v option inverts the match meaning that grep will only print lines that do not match our search pattern. The “^#” pattern matches all lines that begin with a pound sign (#) while the “^$” pattern matches all the blank lines.