select

select.c

 #define csp_without_prefix

 #include <stdio.h>
 #include <libcsp/csp.h>

 chan_declare(mm, int, int);
 chan_define(mm, int, int);

 proc void select1(chan_t(int) *chn, chan_t(int) *chn2) {
   while (true) {
     int num;

     if (chan_try_pop(chn, &num)) {
       printf("Received %d from main channel\n", num);
       return;
     }

     if (chan_try_pop(chn2, &num)) {
       printf("Received %d from main chn2, how odd\n", num);
       return;
     }

     yield();
   }
 }

 proc void select2(chan_t(int) *chn, chan_t(int) *chn3) {
   while (true) {
     if (chan_try_push(chn, 1)) {
       printf("Written 1 to main channel\n");
       return;
     }

     if (chan_try_push(chn3, 1)) {
       printf("Written 1 to ch3, how odd");
       return;
     }

     yield();
   }
 }

 int main(void) {
   chan_t(int) *chn = chan_new(int)(0);
   chan_t(int) *chn2 = chan_new(int)(0);
   chan_t(int) *chn3 = chan_new(int)(0);

   async(select1(chn, chn2); select2(chn, chn3));
   hangup(timer_second);
   
   chan_destroy(chn);
   chan_destroy(chn2);
   chan_destroy(chn3);

   return 0;
 }