How to use grep to exclude lines?

How to use grep to exclude lines?

To exclude particular words or lines, use the –invert-match option. Use grep -v as a shorter alternative. Exclude multiple words with grep by adding -E and use a pipe (|) to define the specific words. Optionally make it case insensitive with the -i as listed above.

How to exclude grep from grep?

3. Excluding grep

1. 3.1. Removing grep With grep. One way to exclude the grep line from ps output is to use an additional grep with the -v option to invert the search: % ps | grep vi | grep -v grep.
2. 3.2. Make a grep Expression That Excludes grep Itself.

How to grep except?

The most simple way to exclude lines with a string or syntax match is by using grep and the -v flag. The output will be the example. txt text file but excluding any line that contains a string match with “ThisWord”. Use whichever works best for your particular workflow.

How do you remove blank lines in Shell?

Simple solution is by using grep (GNU or BSD) command as below.

1. Remove blank lines (not including lines with spaces). grep . file.txt.
2. Remove completely blank lines (including lines with spaces). grep “\S” file.txt.

How to grep inverse match and exclude files?

You could use gnu grep with -A and -B to print exactly the parts of the file you want to exclude but add the -n switch to also print the line numbers and then format the output and pass it as a command script to sed to delete those lines: This should also work with files of patterns passed to grep via -f e.g.:

Is there way to limit the number of lines that grep-V can remove?

I generally prefer removing garbage lines that shouldn’t be there by grep -v ing a reasonably unique string, but the problem with that approach is that if the reasonably unique string appears in the data by accident that’s a serious problem. Is there a way to limit the number of lines that grep -v can remove (say to 1)?

How to exclude the next line after the match?

The N command appends the next line of input to the pattern space (the buffer that sed can edit), and the d deletes the pattern space and starts the next cycle. You can use GNU sed ‘s d command to delete a line, and prefix it with /pat/,+N to select lines matching the pattern and the subsequent N lines.

What does pattern space look like in grep?

…and at the top of the script the N ext input line is retrieved and so the next iteration looks like: And so when we find the first occurrence of 5 in input, the pattern space actually looks like: And when the N ext input line is pulled sed hits EOF and quits. By that time it has only ever P rinted lines 1 and 2.