Distributed computing with single read-single write variables

Single-read-single-write (SRSW) variables are presented for synchronous and asynchronous communication between processes. The operational semantics of the instruction accessing these variables is quite simple: a SRSW variable can be written if it is free, and, once written, it becomes busy. A SRSW variable can be read when busy, and, once read, it becomes free. A process attempting to read a free SRSW variable or write a busy SRSW variable is put in a wait state until the state of the variable changes. The advantages of SRSW variables are multiple. The syntax of a regular sequential language can be used without any change, other than the introduction of a new SRSW data type. Parallel programs tend to be concise and easy to prove correct. The message passing paradigm can be very easily modeled with SRSW variables