Am Mi., 4. März 2020 um 16:31 Uhr schrieb Marc Feeley <>:

> On Mar 4, 2020, at 10:12 AM, Lassi Kortela <> wrote:
>> I think the I/O methods should be extended with the following features
>> 1) a “transfer up to N bytes/characters that are currently available” method that returns the number of bytes/characters that have been transferred (0 when nothing is available)
>> 2) a “transfer at least N bytes/characters” method with an optional timeout parameter indicating how long to wait for N bytes to become available, and return the number of bytes transferred
>> These could probably be combined in the same method with many parameters.
> Are you suggesting these for SRFI 181 specifically, or for Scheme in general?

It is a dream that Scheme have such a feature, but it really requires threads to maximize their usefulness so I’m not sure which RnRS we’re talking about.  Perhaps it is time to think about adding SRFI 18 to Scheme… it has seen close to 20 years of experience in the field and is supported by many implementations of Scheme.

+1 to adding SRFI 18 to Scheme (R7RS-large).

If R7RS-large is to become a language for practical programming, it cannot do without threads nowadays. (With threads, I would also like to see mutable parameter objects in R7RS-large that function like thread-local variables in other programming languages.)

-- Marc