How do you remove the last line of a file in Unix?
So sed ‘$d’ file; sed ‘$d’ file will print out the contents of the file twice, minus the last line each time. The delete-the-last-two-lines equivalent of sed ‘$d’ file is sed ‘$d’ file | sed ‘$d’ . Yeah, that’s inelegant but of course it works.
How do I remove a line in Unix?
To Remove the lines from the source file itself, use the -i option with sed command. If you dont wish to delete the lines from the original source file you can redirect the output of the sed command to another file.
How do you delete the first and last line in Unix?
How it works :
- -i option edit the file itself. You could also remove that option and redirect the output to a new file or another command if you want.
- 1d deletes the first line ( 1 to only act on the first line, d to delete it)
- $d deletes the last line ( $ to only act on the last line, d to delete it)
How do you remove the last line of a file?
You can remove the newline character at the end of file using following easy way:
- head -c -1 file. From man head : -c, –bytes=[-]K print the first K bytes of each file; with the leading ‘-‘, print all but the last K bytes of each file.
- truncate -s -1 file.
How do you remove multiple lines in Unix?
Deleting Multiple Lines
- Press the Esc key to go to normal mode.
- Place the cursor on the first line you want to delete.
- Type 5dd and hit Enter to delete the next five lines.
How do I remove the first line in Unix?
Using the sed Command
Removing the first line from an input file using the sed command is pretty straightforward. The sed command in the example above isn’t hard to understand. The parameter ‘1d’ tells the sed command to apply the ‘d’ (delete) action on line number ‘1’.
How do I remove the last 10 lines in Unix?
It’s a little roundabout, but I think it’s easy to follow.
- Count up the number of lines in the main file.
- Subtract the number of lines you want to remove from the count.
- Print out the number of lines you want to keep and store in a temp file.
- Replace the main file with the temp file.
- Remove the temp file.
How do I delete a line in CMD?
Go to beginning of the line: Ctrl + A. Go to end of the line: Ctrl + E. To clear your entire command prompt: Ctrl + L.
How do I remove a grep line?
Use the grep command to delete the line containing the specified string. Grep command, we use it more to match the specified string in the text file. Since it can be matched, it can also be excluded, you need to use the grep -v option.
How do I remove the last 10 lines in Linux?
Remove the Last N Lines of a File in Linux
- awk.
- head.
- sed.
- tac.
- wc.
What is the use of awk in Linux?
Awk is a utility that enables a programmer to write tiny but effective programs in the form of statements that define text patterns that are to be searched for in each line of a document and the action that is to be taken when a match is found within a line. Awk is mostly used for pattern scanning and processing.