Seq Command in Linux: Linux seq command generates a list of numbers – you can use this in scripts and many other functions. Let’s see the examples.
Basic usage of command
Just typing seq 5 will create 5 numbers
[root@server ~]# seq 10
1
2
3
4
5
[root@server ~]#
If you type two numbers, the first number will be the start and another one will be the end number.
[root@server ~]# seq 21 25
21
22
23
24
25
[root@server ~]#
You can add a third number in between which will work as a step.
for example, if you type seq 5 5 50 it will generate a number from 5 to 50 at the interval of 5 – see the example below
[root@server ~]# seq 5 5 50
5
10
15
20
25
30
35
40
45
50
[root@server ~]#
You can generate numbers in descending order as well by adding the middle number in -ve
[root@server ~]# seq 10 -1 1
10
9
8
7
6
5
4
3
2
1
Practical Usage of seq command
First, let’s see how to create files using the seq command. You will need to use format strings functions i.e. -f
[root@server seq]# touch $(seq -f "file-%g.txt" 1 10)
See the output of the command above.
You can use the seq command in your scripting for example while Loops or For Loops.
We will see an example for the loop.
[root@server seq]# for i in $(seq 1 10); do echo "Hello $i"; done
Hello 1
Hello 2
Hello 3
Hello 4
Hello 5
Hello 6
Hello 7
Hello 8
Hello 9
Hello 10
Here is Man page you can use it to learn something more about it which may be covered in this page.