Re: mutexes and const_iterators

Barry <>
Sat, 15 Mar 2008 05:50:33 -0700 (PDT)
On 3=D4 15=C8=D5, =CF =CE=E76=CA=B121=B7=D6, "Angus" <> =


I am using a map which holds a list of client connections (to a server).
When a client connects a client gets added to the map and also when a clie=



In various parts of the code the map gets updated - the key is an int and
the value is a class.

As the map may be accessed by multiple threads I use a mutex to control
access - ie locking whenever an item is added or removed.

I have these questions:

1. Do I also need to lock if I just update and item? I access the item vi=


an iterator.

2. Do I need to lock if I simply access the map via a const_iterator?

I think this is a reader-writer problem, nothing specific with /map/.

one note:
The insert members shall not affect the validity of iterators
and references to the container, and the erase members shall
invalidate only iterators and references to the erased elements

Best Regards

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