Single command to create a file and set its permission

Question

I am using the following 2 commands to create a 0B file and set its extn to 644

touch filename.ext
chmod 777 filename.txt

My question is that w

Answer 1

For bash, simply use chmod with file redirection and history expansion:

chmod 777 filename.txt>>!#:2

For ksh and zsh you have to drop the history expansion (as shown above, there may be other ways) and use:

chmod 644 filename>>filename

For scripts of any shell you don't have (and really don't need) history expansion so use the above there as well.