linux - how to make a shell script that duplicates each line of input

Home>2019-12-08 10:33

When multiple lines of input are given, I want to create a one-line command that outputs a copy of each line down one line.

Specifically, for example, the output offind ./ ．-type fis

aaa.txt
bbb.txt
ccc.txt

and when this is received as input on a pipe

aaa.txt
aaa.txt
bbb.txt
bbb.txt
ccc.txt
ccc.txt

I want to output

I would appreciate it if you could tell me what command to use.
Thank you.

This is a postscript.
OS: Cent OS7
Shell: bash

Answer # 1
Sorry if you can't execute it because you don't know the execution environment.
I think there are various ways, but I think the following means can be realized simply.
```
## using sed
$find -type f | sed p
```
```
## using awk
$find -type f | awk '1;1'
```