Call a function before function exits

Question

I will begin with an example. Suppose I need to guard a code with a function inside a mutex. There are two ways of implementing this.

#include 
#         


        

Answer 1

Here's an example using Boost.ScopeExit (untested):

#include 

...

void threadfunc_autolock(int i, float value)
{
    pthread_mutex_lock(&myMutex);

    BOOST_SCOPE_EXIT(&myMutex) {
        pthread_mutex_unlock(&myMutex);
    } BOOST_SCOPE_EXIT_END

    if(i <= 0 || i > myVec.size())
    {
        return;
    }

    if(value < 0)
    {
        return;
    }

    myVec[i] += value;
}