Hello PLUG

Happy 4th of July

i'm looking for an explanation of how mutex works with apache web servers
specifically when the mutex directive is set to sysvsem (SystemV semaphore)

the wikipedia article below is nice but i'm still having a hard time 
understanding

https://en.wikipedia.org/wiki/Semaphore_%28programming%29

if it is even possible for someone who has the patience to do it, i'd 
like the explanation to go
like something like this (given that apache is set to prefork MPM):

apache starts
apache starts StartServers child processes (lets say process #1 is created)
a request on port 80 is passed to one of the children created above 
(lets say to process #1)
another child process, (this is done until MaxSpareServers is reached)
a semaphore is created by the parent apache process for the HTTP request 
and is given to process #1,
the semaphore locks a certain amount of shared memory
process #1 opens a TCP outbound connection to the host
process #1 processes the request, sends data to the socket
process #1 closes the socket
process #1 signals the parent that the request is complete and is ready 
for next request
parent takes back the semaphore



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