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#include <stdlib.h>
#include <ucontext.h>
#include <unistd.h>
int foo(ucontext_t *old, ucontext_t *new)
{
swapcontext(old, new);
}
int bar(int c)
{
return c + getpid();
}
int baz(volatile int c)
{
return c % 2;
}
#define STACKSIZE 8192
int main(int argc, char *argv[])
{
int n = 10;
char stack[STACKSIZE];
ucontext_t curr, new;
if (argc > 1)
n = atoi(argv[1]);
getcontext(&new);
new.uc_link = &curr;
new.uc_stack.ss_sp = stack;
new.uc_stack.ss_size = STACKSIZE;
makecontext(&new, (void (*)(void))bar, 1, n);
foo(&curr, &new);
n = baz(n);
return !(n < 2);
}
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