Linux futex for 64-bit
I’m on a 64-bit Linux machine:
Linux illin793 2.6.32-279.5.2.el6.x86_64 #1 SMP Tue Aug 14 11:36:39
EDT 2012 x86_64 x86_64 x86_64 GNU/Linux
From man futex:
int futex(int *uaddr, int op, int val, const struct timespec *timeout,
int *uaddr2, int val3);
So, futex here uses 32-bit values.
Is there a futex on Linux that supports 64-bit values?
Linux does not currently support 64-bit futexes. There were patches circulating back in 2007 to add support, but I don’t know why they weren’t integrated.