On Tue, Dec 3, 2019 at 6:31 PM Liam <networkimp...@gmail.com> wrote:
>
> Erm... not seeing how cas works to try a read-lock, which admits multiple
> callers...
Something like this should work:
TryLock:
if CompareAndSwap(&v,0,1) {
door.Lock()
return true
}
return false
Unlock:
door.Unlock()
Store(&v,0)
>
> On Tuesday, December 3, 2019 at 5:12:08 PM UTC-8, Robert Engels wrote:
>>
>> Can’t code on the phone but a cas on the atomic then take the lock. But if
>> you never need to block you don’t even need the lock.
>>
>> On Dec 3, 2019, at 6:52 PM, Liam Breck <networ...@gmail.com> wrote:
>>
>>
>> Which looks like...?
>>
>> On Tue, Dec 3, 2019, 4:50 PM Robert Engels <ren...@ix.netcom.com> wrote:
>>>
>>> I would use an atomic and a lock instead of two locks.
>>>
>>> > On Dec 3, 2019, at 6:35 PM, burak serdar <bse...@computer.org> wrote:
>>> >
>>> > On Tue, Dec 3, 2019 at 5:21 PM Liam Breck <networ...@gmail.com> wrote:
>>> >>
>>> >> I have a problem that is trivially solved via
>>> >>
>>> >> door sync.RWMutex
>>> >>
>>> >> func Reader() T {
>>> >> if !door.TryRLock() { // missing in stdlib :-(
>>> >> return busy
>>> >> }
>>> >> defer door.RUnlock()
>>> >> ...
>>> >> }
>>> >>
>>> >> func Writer() {
>>> >> door.Lock()
>>> >> defer door.Unlock()
>>> >> ...
>>> >> }
>>> >>
>>> >> How does one achieve this in Go?
>>> >
>>> > Two locks and a bool?
>>> >
>>> > var door=sync.Mutex{}
>>> > var x=sync.Mutex{}
>>> > var b bool
>>> >
>>> > func trylock() bool {
>>> > x.Lock()
>>> > if b {
>>> > x.Unlock()
>>> > return false
>>> > }
>>> > b=true
>>> > door.Lock()
>>> > x.Unlock()
>>> > return true
>>> > }
>>> >
>>> > unlock:
>>> >
>>> > x.Lock()
>>> > b=false
>>> > door.Unlock()
>>> > x.Unlock()
>>> >
>>> >
>>> >
>>> >
>>> >>
>>> >> --
>>> >> You received this message because you are subscribed to the Google
>>> >> Groups "golang-nuts" group.
>>> >> To unsubscribe from this group and stop receiving emails from it, send
>>> >> an email to golan...@googlegroups.com.
>>> >> To view this discussion on the web visit
>>> >> https://groups.google.com/d/msgid/golang-nuts/CAKvHMgTO%3DxfFQ_u7aO9UE-1vHHEKmdhr47sro2mnp6DkEb6mPA%40mail.gmail.com.
>>> >
>>> > --
>>> > You received this message because you are subscribed to the Google Groups
>>> > "golang-nuts" group.
>>> > To unsubscribe from this group and stop receiving emails from it, send an
>>> > email to golan...@googlegroups.com.
>>> > To view this discussion on the web visit
>>> > https://groups.google.com/d/msgid/golang-nuts/CAMV2RqrDeBNhkeswg%2BhdCf1kSzMEJduota%3D6UrNq4z2PQRtzEQ%40mail.gmail.com.
>>>
> --
> You received this message because you are subscribed to the Google Groups
> "golang-nuts" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to golang-nuts+unsubscr...@googlegroups.com.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/golang-nuts/2d284bfc-3916-425a-9dd1-59b216ef23e2%40googlegroups.com.
--
You received this message because you are subscribed to the Google Groups
"golang-nuts" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to golang-nuts+unsubscr...@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/golang-nuts/CAMV2RqqsFo1wxsP_P9iacNNP2DR%2BPut4TwcfKtcun4Oy9CJbEA%40mail.gmail.com.
