Linux head skip lines

Print file content without the first and last lines

Is there a simple way I can echo a file, skipping the first and last lines? I was looking at piping from head into tail , but for those it seems like I would have to know the total lines from the outset. I was also looking at split , but I don’t see a way to do it with that either.

5 Answers 5

Just with sed , without any pipes :

• 1 mean first line
• d mean delete
• ; is the separator for 2 commands
• $ mean last line

You don’t need to know the number of lines in advance. tail and head can take an offset from the beginning or end of the file respectively.

This pipe starts at the second line of the file (skipping the first line) and stops at the last but one (skipping the final line). To skip more than one line at the beginning or end, adjust the numbers accordingly.

tail -n +2 file.txt | head -n -1 

doing it the other way round, works the same, of course:

head -n -1 file.txt | tail -n +2 

I don’t know why, but head -n -1 removes the first AND the last line of my .txt file, on Ubuntu 14.04.2LTS.

Here is how to do it with awk :

x is advanced sed command, it switches current line with the previous one: current goes into the buffer and previous goes to the screen and so on while sed processing stream line by line (this is why the first line will be blank).

awk solution on each step (line) puts current line into the variable and starts printing it out only after the second line is passed by. Thus, we got shitfed sequence of lines on the screen from the second to the last but one. Last line is omitted becasue the line is in the variable and should be printed only on the next step, but all steps already run out and we never see the line on the screen.

perl -ne 'print $t if $.>2 ; $t=$_' file.txt 

$. stands for line number and $_ for current line.
perl -n is shortcut for while() structure and -e is for inline script.

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How to Skip the First Line of a File Using ‘awk’

The following `awk` command uses the ‘-F’ option and NR and NF to print the book names after skipping the first book. The ‘-F’ option is used to separate the content of the file base on \t. NR is used to skip the first line, and NF is used to print the first column only.

1. How do I skip the first line of a file?
2. How do I ignore the first line in Linux?
3. How do you skip a line in a shell script?
4. How do you cut the first line of a file in Unix?
5. How do you skip the first line of a file in Python?
6. How do I skip the first line of a csv file in Python?
7. What is NR in awk command?
8. How do you delete the first and last line in Unix?
9. How do you print the first line of AWK in Unix?
10. How do I remove the first line from a csv file in Unix?
11. How do I print all lines except first in Unix?
12. How do I ignore a line in Linux?

How do I skip the first line of a file?

1. a_file = open(«example_file.txt»)
2. next(a_file)
3. for line in a_file:
4. print(line. rstrip())
5. a_file. close()

How do I ignore the first line in Linux?

$ tail -n + < filename, excluding first N lines. >That is, if you want to skip N lines, you start printing line N+1. Example: $ tail -n +11 /tmp/myfile < /tmp/myfile, starting at line 11, or skipping the first 10 lines. >

How do you skip a line in a shell script?

Using head to get the first lines of a stream, and tail to get the last lines in a stream is intuitive. But if you need to skip the first few lines of a stream, then you use tail “-n +k” syntax. And to skip the last lines of a stream head “-n -k” syntax.

How do you cut the first line of a file in Unix?

1. Delete First two charters in lin sed ‘s/^..//’ file.
2. Delete last two chrecters in line sed ‘s/..$//’ file.
3. Delete blank line sed ‘/^$/d’ file.

How do you skip the first line of a file in Python?

Use string slicing on file. readlines() to skip the first few lines of a file. To read a file, open the file in read only mode by calling open(file, mode) with the filename as file and mode as «r» .

How do I skip the first line of a csv file in Python?

1. file = open(‘sample.csv’)
2. csv_reader = csv. reader(file)
3. next(csv_reader)
4. for row in csv_reader:
5. print(row)

What is NR in awk command?

NR is a AWK built-in variable and it denotes number of records being processed. Usage : NR can be used in action block represents number of line being processed and if it is used in END it can print number of lines totally processed. Example : Using NR to print line number in a file using AWK.

How do you delete the first and last line in Unix?

1. -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.
2. 1d deletes the first line ( 1 to only act on the first line, d to delete it)
3. $d deletes the last line ( $ to only act on the last line, d to delete it)

How do you print the first line of AWK in Unix?

1. awk NR==1 , or do you have to only print the name? awk -F: ‘NR==1print $2’ – Kevin Jan 29 ’12 at 22:59.
2. And in case the file is very big, it can be good to do awk ‘NR==1 print; exit’ so the file is not read any more after the first line. – fedorqui ‘SO stop harming’ May 12 ’14 at 8:24.

How do I remove the first line from a csv file in Unix?

How do I print all lines except first in Unix?

tail -r : reverses the order of lines in its input. tail -n +2 : prints all the lines starting from the second line in its input.

How do I ignore a line in Linux?

To ignore some lines on a line-by-line basis, add /unwanted pattern/ next or ! /wanted pattern/ next at the beginning of the script.

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Print File After Skipping First X Lines in Bash

1. Skip Lines Using the head and tail Commands
2. Use vim to Skip First n Lines
3. Use sed to Skip First n Lines

Suppose you have a file, a huge one, and you want to display its contents. How would you go about it?

You obviously wouldn’t want to print out the file’s entire contents as that wouldn’t be very practical. You would want to print some selective lines; maybe you’d use regular expressions to parse the file and only print the matches.

This article will explain several methods to do so.

Skip Lines Using the head and tail Commands

The below example uses the five most commonly used Bash commands to do so:

tail fileName.txt head fileName.txt tail -n fileName.txt # here n is an integer head -n fileName.txt # here n is an integer tail +n fileName.txt # prints all lines starting from # the nth file 

What the tail command does is that it prints the last ten lines of a file, while the head prints the first ten lines of a file.

When you use the tail command with the –n option, it prints the last n lines. Conversely, when you use the head command with the –n option, it prints the first n lines.

It is important to note that here n is an integer, so when you execute the commands, you will have to substitute n with an integer.

The fifth method is somewhat tricky. It ignores the first (n – 1) lines and prints all the lines after that.

Use vim to Skip First n Lines

You could also use the Vim editor to skip the first n lines. Vim is a console-based text editor that allows you to create and change any text document highly efficiently.

To first use Vim, you must install it. Use the command below to do so:

Now that Vim is installed, we get to the business part of our purpose, which is using Vim to skip the first n lines.

We will do it by using an intermediary file. We will first copy the contents of our old file to a new one; then, we will delete the new file’s first n lines.

We will use input and output redirection to copy the contents of one file to another. If you have studied the operating system course, you would have heard of the ppfdt table (process file descriptor table).

By default, the first descriptor points to stdin (or keyboard), the second descriptor points to stdout (or monitor), and the third descriptor points to stderror .

Consider the script below for further understanding.

cat 0new_file.txt # copies old file’s contents to new file 

The above command reads the contents of the old file and copies it to the new file. Notice how we use the descriptor 0 to read and the descriptor 1 to write.

If you find this descriptor confusing, we’ve got something different for you. The below commands will work too:

cat new_file.txt # copies old file’s contents to new file cp new_file.txt # copies old file’s contents to new file 

Please notice that in the second method above, we’ve used the copy command (i.e., cp ). It takes two arguments: the path to the source file and the path to the destination file.

Now that we’re done copying the file. Open the new file in Vim and use the below command:

Now use Shift + Esc and type the following command in Vim:

:1,nd # here n is an integer number e.g., 2 

The above command deletes the first n lines in the new_file.txt . Here, d stands for delete.

Use sed to Skip First n Lines

Creating a new file and then deleting its contents can be a hassle. Furthermore, it will also consume a lot of extra memory if the old file is huge.

So, let’s see an easier method to achieve the same:

sed 1,nd old_file.txt # here n is an integer 

It is important to note that the sed command will not modify the old file. Rather, it will simply display the contents of the old file after removing the first n lines.

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