allow reading without "hanging"

[felix winkelmann]

(suggested by Alejandro)

It would be nice to have a "read as much of input as is currently available" type of read-string[!], say,

(read-string/no-hang NUM [PORT]) -> STRING (may be shorter than NUM)
(read-string!/no-hang NUM STRING [PORT [START]]) -> NUM'

This could probably be implemented using another port method, defaulting to char-ready? + read-char.

[felix winkelmann]

I have added a (currently undocumented) procedure that may be helpful:

(read-buffered [PORT]) -> STRING

This returns any currently buffered input from the given port, or "" if nothing is buffered or the port does not support buffering.

[Jim Ursetto]

Older versions of chicken will raise an error when providing the read-buffered argument to make-input-port, and we cannot know when it is safe to do so. Would you mind adding some sort of feature identifier or other way to determine when read-buffered is a legal optional argument? This would help when create advanced custom ports.

[felix winkelmann]

We can not add a feature-identifier for each and every enhancement made in the core libraries (there already are too many defined anyway). I suggest checking the chicken version or something like that, which is ugly but scales somewhat better.

I'd like to close this ticket and ignore the problem until someone complains.

[Jim Ursetto]

OK.