Re: [boost] Boost.Threads Locking Delima

From: Victor A. Wagner, Jr. (vawjr_at_[hidden])
Date: 2002-05-19 16:04:23

At Sunday 2002/05/19 12:00, you wrote:
>>From: "Victor A. Wagner, Jr." <vawjr_at_[hidden]>
>>To use an analogy that's been in use for decades to save human lives:
>>At large construction sites where various electrical work  will be going
>>on, there is a shutoff which can be locked _open_ simply by putting a
>>common padlock on it.  The "hole" for the padlock to secure is large enough
>>for many locks.  When an electrician comes to work and needs the power
>>killed, s/he simply adds his/her personal lock.  When done, one removes
>>one's own lock and leaves.  The power cannot be restored until ALL the
>>locks are gone.
>
>This analogy is flawed.  Given your description the "hole" would be the 
>mutex, the padlocks would be the scoped_locks and the electricians would 
>be threads.  Mutexes, by definition, don't allow multiple threads to have 
>access to a shared resource.  Though this synchronization scheme may be 
>valid, it's not analogous to what's being discussed here.

Apologies, I understand that when hampered with all the safety built into 
mutex, it may not be possible.
It's why mentioned regret that semaphores had been dropped as "too dangerous"

>Bill Kempf
>williamkempf_at_[hidden]
>
>
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Victor A. Wagner Jr.      http://rudbek.com
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