File I/O

f puts the interpreter into file mode, meaning the next command does something with files.

Getting data from a file

Let's say you have a file named stuff.txt and you want to get the text from that file. You can using fi

stuff.txt contains:

I like cheese

We'll use this to push the contents of the file to the stack (assuming that stuff.txt is in the same directory):


The stack now contains the string “I like cheese”.

Putting data in a file

Using fo, we can overwrite whatever is in a file with what is on the stack.

"I don't like cheese""stuff.txt"fo

Anything that was in stuff.txt is now gone, and it only contains “I don't like cheese”. fo will only put the second item on the stack into the file, no other elements will be affected.