On Feb 18, 2013, at 3:58 AM, J Altfas wrote: > Certainly agree that leaving out usleep was an oversight, considering how > simple it is to include it. While I'm pretty sure many of the posix functions > are not optimum in an srfi-18 threaded environment, file-select, sleep, and > friends are still part of Chicken for good reasons. In that sense, I don't > think thread-sleep! would be a universal drop-in replacement for posix > usleep, et. al.
It's probably not an oversight, just that as Felix said there was probably no usleep(3) in Windows and the equivalent was never implemented. Also since file-select works, there was probably no impetus to fix it. I would be ok with adding usleep to the posix-extras egg if you want. I'm not sure if it should be a separate function or just override (sleep) to accept fractional values. I'm thinking the latter. I would ideally want to get it to work on Windows, maybe using John Cowan's suggestion (which gives at most millisecond precision, so "usleep" is not a good name) or QueryPerformanceCounter (?). By the way, on Windows, (sleep t) is currently implemented as Sleep(t*1000), but the argument is artificially constrained to be an integer. If you just want a direct interface to usleep, I would honestly just wrap it in a foreign-lambda in your code as you suggested. I don't think it's a bad approach. > As long as file-select is available in Chicken, people are going to have uses > for it. As it is, the current types.db declaration for file-select produces > several warnings. I was a little concerned the warnings might be distressing > for new Chicken users, though more a matter of technical details than truly > having dire consequences for the compiled output. Yes, erroneous warnings should definitely be fixed. I didn't intend to address that in my reply. file-select is actually a reasonable solution if you want a blocking sub-second sleep, although it too doesn't work on Windows. Jim _______________________________________________ Chicken-users mailing list Chicken-users@nongnu.org https://lists.nongnu.org/mailman/listinfo/chicken-users
