d is the sed command to delete a line. ^$ is a regular expression matching only a blank line, a line start followed by a line end. You can use the -v option with grep to remove the matching empty lines. With Awk, NF only set on non-blank lines.
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How do I remove a specific 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 I delete a specific line in Linux?
You can use the “stream editor for filtering and transforming text” sed. Here, -i means edit the file inplace. d is the command to “delete the pattern space; immediately start next cycle”.
The right tool for the job
- tr -d ‘ ‘ < input.txt > no-spaces.txt.
- tr -d ‘[:blank:]’ < input.txt > no-spaces.txt.
- tr -d ‘[:space:]’ < input.txt > no-spaces.txt.
16 окт. 2014 г.
How do I remove the first 10 lines in Unix?
Remove first N lines of a file in place in unix command line
- Both sed -i and gawk v4.1 -i -inplace options are basically creating temp file behind the scenes. IMO sed should be the faster than tail and awk . – …
- tail is multiple times faster for this task, than sed or awk . ( of course doesn’t fit for this question for real inplace) – thanasisp Sep 22 ’20 at 21:30.
27 июн. 2013 г.
How do I remove the last 10 lines in Unix?
Remove the Last N Lines of a File in Linux
- awk.
- head.
- sed.
- tac.
- wc.
8 нояб. 2020 г.
How do I remove the first line in Unix?
To delete a charecter in a line
- Delete First two charters in lin sed ‘s/^..//’ file.
- Delete last two chrecters in line sed ‘s/..$//’ file.
- Delete blank line sed ‘/^$/d’ file.
How do I delete a line in CMD?
2 Answers. The Escape ( Esc ) key will clear the input line. In addition, pressing Ctrl+C will move the cursor to a new, blank line.
How do I count the number of blank lines in a file in Unix?
I cat file; apply grep with -v (exclude from enumerated) and [^$] (final line, contents “null”). Then I pipe for wc , parameter -l (just count lines). Done.
How do I remove spaces from text files?
The easy way would be select everything (Ctrl+A), go to Edit>Blank Operation>Trim Trailing Space. This should remove all the spaces in between.
How do I ignore space in Linux?
We use s* for 0 or more whitespace (so will include tabs etc.) and s+ for 1 or more whitespace.
How do I count the number of lines in a file in Linux?
The most easiest way to count the number of lines, words, and characters in text file is to use the Linux command “wc” in terminal. The command “wc” basically means “word count” and with different optional parameters one can use it to count the number of lines, words, and characters in a text file.
How do I move the first 10 files in UNIX?
- Goto the directory which you want to move files from.
- run below command find . – name ‘Hello*.gz’ | head -n 5000 | xargs -I {} mv {} /data01/path/
What is use of tail command in Linux?
The tail command is a command-line utility for outputting the last part of files given to it via standard input. It writes results to standard output. By default tail returns the last ten lines of each file that it is given. It may also be used to follow a file in real-time and watch as new lines are written to it.
