One command to create a directory and file inside it linux command

Question

Suppose my current directory is A. I want to create a directory B and a file "myfile.txt" inside B.

How to do that in one command from Terminal?

Edit:

Directory can be nested multiple times. Like I may want to create B/C/D and then "myfile.txt" inside that. I do not also want to repeat the directory part.

Following command will create directory at any level.

mkdir -p B/C/D  

and

mkdir -p B/C/D && touch B/C/D/myfile.txt 

will create the directory and the file. But I do not want to repeat the directory part after the touch command. Is that possible?

Answer 1

mkdir B && touch B/myfile.txt 

Alternatively, create a function:

mkfile() { mkdir -p -- "$1" && touch -- "$1"/"$2" } 

Execute it with 2 arguments: path to create and filename. Saying:

mkfile B/C/D myfile.txt 

would create the file myfile.txt in the directory B/C/D.