If you want to protect your file txt (or whatever) with a password you can use the command mcrypt like in the example:

$ mcrypt data.txt

It will generate a file data.txt.nc protected by a password that you insert during the encryption, well, to decrypt and read the content you should type:

$ mcrypt -d data.txt.nc

it will generate a file data.txt with the content of data.txt.nc, so to read and protect your data, you should open the file data.txt and delete it.

I made the shell function catcrypt to decrypt, get the content of the file txt (with the cat command) and delete it with just one command.

Just add this code in your file ~/.bashrc (if this file doesn't exist create it with $ touch ~/.bashrc) and restart your terminal or use $ source ~/.bashrc

# decrypt netCDF, read and delete
catcrypt() {
	file=$@
	mcrypt -d $file
	cat "${file::-3}"
	rm "${file::-3}"
}
alias catcrypt=catcrypt

example:

$ catcrypt data.txt.nc

it will print in your terminal the content decrypted of data.txt.nc b