Mastering Go - Second Edition

Shared memory and shared variables

Shared memory and shared variables are the most common ways for UNIX threads to communicate with each other.

A mutex variable, which is an abbreviation of mutual exclusion variable, is mainly used for thread synchronization and for protecting shared data when multiple writes can occur at the same time. A mutex works like a buffered channel with a capacity of one, which allows at most one goroutine to access a shared variable at any given time. This means that there is no way for two or more goroutines to try to update that variable simultaneously.

A critical section of a concurrent program is the code that cannot be executed simultaneously by all processes, threads, or, in this case, goroutines. It is the ...