See http://www.1024cores.net/home/lock-free-algorithms/tricks/fibers http://www.1024cores.net/home/lock-free-algorithms/tricks/fi... on ucontext And for longjm

See http://www.1024cores.net/home/lock-free-algorithms/tricks/fibers http://www.1024cores.net/home/lock-free-algorithms/tricks/fi... on ucontext And for longjmp, Apple source for example https://opensource.apple.com/source/Libc/Libc-262/i386/sys/setjmp.s.auto.html https://opensource.apple.com/source/Libc/Libc-262/i386/sys/s.... It does seem like glibc impl doesn't involve syscalls: https://groups.google.com/forum/#!topic/comp.unix.programmer/LvUP9H-7Aes https://groups.google.com/forum/#!topic/comp.unix.programmer...