Michele Simionato <[EMAIL PROTECTED]> wrote: > On May 8, 4:53 am, [EMAIL PROTECTED] (Alex Martelli) wrote: > > What do you expect from "timers on Linux" that you could not get with a > > simple "sleep for the next N milliseconds"? A timer (on Linux or > > elsewhere) can jog your process N milliseconds from now, e.g. with a > > SIGALRM or SIGPROF, and you can set one with the setitimer syscall > > (presumably accessible via ctypes, worst case -- I've never used it from > > Python, yet), but how would that help you (compared to plain sleep, > > select, poll, or whatever else best fits your need)? > > I hoped there was a library such thay I could register a Python > callable (say > a thunk) and having it called by the linux timer at time t without > blocking > my process. But if a Linux timer will just send to my process an > alarm, I would need to code myself a mechanism waiting for the alarm > and doing the function call. In that case as you say, I would be > better off with a select+timeout or a even with a queue+timeout, which > already do most of the job.
Python or not, I don't know of a way to "register a callback" from the OS without using threads. Considering that your callback WOULD be executing on a different thread no matter what (your "only" thread being blocked on some blocking syscall, or executing other code -- having other code in your process suddenly start executing at that point is pre-emptive threading, by whatever name you choose to call it), it's not clear to me why the "avoiding threads" issue should matter to you. Alex -- http://mail.python.org/mailman/listinfo/python-list
