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/!\ Incomplete.
[[!map pages="microkernel/mach/gnumach/interface/*"
show=title]]
# Proposed
## <a name="futex">Futex</a>
Add a futex kernel trap to GNU Mach.
This can be useful for nicer locking
primitives, including inter-process primitives. `vm_allocate` can be used as an
example in the `gnumach` source tree for how to add a kernel trap.
### [[!GNU_Savannah_task 6231]]
### Patches on bug-hurd
### IRC, freenode, #hurd, 2014-01-20
<teythoon> braunr: i meant to ask about the futex stuff
<teythoon> what do you mean when you talk about the interface ?
<teythoon> i imagined something like this
<braunr> more precisely ?
<teythoon> for shared futexes, do not use a pointer, but a right
referencing a memory object, and the offset ?
<braunr> why not a pointer ?
<braunr> well, an address
<teythoon> that's how it's currently done, right ?
<teythoon> in marins prototype i mean
<braunr> yes
<braunr> it's a task/address pair
<teythoon> so the only concern is the access in the kernel ?
<braunr> hum not only no
<braunr> or yes, but there are multiple ways to access
<teythoon> i meant to say this, for me, it would be very helpful if you
were more explicit when you describe how you picture something
<braunr> i thought i did it clearly
<braunr> i even agree with what roland describes
<braunr> which looks even clearer
<braunr> also, i said i didn't picture it completely
<braunr> :)
<braunr> i didn't want to work on that, only review
<teythoon> sure, but what might be clear to you is most likely not that
clear to me
<braunr> ok
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