How to read mutliline input from stdin into variable and how to print one out in shell(sh,bash)?

How to read mutliline input from stdin into variable and how to print one out in shell(sh,bash)?

bash shell stdin multiline

bash

How to Export a Multi-line Environment Variable in Bash/Terminal e.g: RSA Private Key

bash shell environment-variables multiline private-key

bash

Bash: split long string argument to multiple lines?

bash multiline

bash

How to execute multiline python code from a bash script?

python bash multiline

bash

How to output a multiline string in Dockerfile with a single command

string bash docker dockerfile multiline

bash

sed replace line with multiline-variable

bash sed multiline

bash