Print a file, skipping the first X lines, in Bash

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I have a very long file which I want to print, skipping the first 1,000,000 lines, for example.

I looked into the cat man page, but I did not see any option to do this. I am looking for a command to do this or a simple Bash program.

13 Answers

You'll need tail. Some examples:

$ tail great-big-file.log
< Last 10 lines of great-big-file.log >

If you really need to SKIP a particular number of "first" lines, use

$ tail -n +<N+1> <filename>
< 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. >

If you want to just see the last so many lines, omit the "+":

$ tail -n <N> <filename>
< last N lines of file. >

If you have GNU tail available on your system, you can do the following:

tail -n +1000001 huge-file.log

It's the + character that does what you want. To quote from the man page:

If the first character of K (the number of bytes or lines) is a `+', print beginning with the Kth item from the start of each file.

Thus, as noted in the comment, putting +1000001 starts printing with the first item after the first 1,000,000 lines.

Use:

sed -n '1d;p'

This command will delete the first line and print the rest.

You can do this using the head and tail commands:

head -n <num> | tail -n <lines to print>

where num is 1e6 + the number of lines you want to print.

This shell script works fine for me:

#!/bin/bash
awk -v initial_line=$1 -v end_line=$2 '{
    if (NR >= initial_line && NR <= end_line) 
    print $0
}' $3

Used with this sample file (file.txt):

one
two
three
four
five
six

The command (it will extract from second to fourth line in the file):

edu@debian5:~$./script.sh 2 4 file.txt

Output of this command:

two
three
four

Of course, you can improve it, for example by testing that all argument values are the expected :-)

I needed to do the same and found this thread.

I tried "tail -n +, but it just printed everything.

The more +lines worked nicely on the prompt, but it turned out it behaved totally different when run in headless mode (cronjob).

I finally wrote this myself:

skip=5
FILE="/tmp/filetoprint"
tail -n$((`cat "${FILE}" | wc -l` - skip)) "${FILE}"
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