How to read characters from stdin?

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Hello,

I am just starting to learn Forth. I appreciate the efforts put to produce=
 and maintain this nice package.

I wanted to write a simple program that reads input from stdin, and writes=
 it out to stdout doing a little translation.

At first I thought I could make use of key and key?, but I see the documen=
tation indicates this can't be used on stdin.

So, I tried read-line. This works mostly. I can read characters one at a t=
ime, and the main program's begin ... while loop will terminate at EOF. Bu=
t, as one would expect by something called read-line, it consumes returns =
on its own. I'd like to receive those.

Then I tried a combination of read-file and read-line with:

chr 0 stdin read-line

hoping to get the flag to know whether the end of the input has been reach=
ed (which read-file doesn't provide), but this doesn't work either, and th=
e program hangs indefinitely.

In case it matters, I'm actually running this on a phone running Lineage O=
S (ostensibly Android) under termux. I don't think it effects the behavior=
.

I did find something on rosettacode:

https://rosettacode.org/wiki/Copy_stdin_to_stdout#Forth

So I am currently using slurp-fid to dump all of stdin into memory, and th=
en reading a character out and updating the address pointer as I go.

But I was wondering if it is possible to do this from just reading charact=
ers directly from the file descriptor. Is there some other check for EOF I=
 missed in the documentation?

Thanks for reading.
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