If multiple processes write messages to the same named pipe, the messages might be interleaved (mixed). However, as stated earlier, individual message reads and writes are atomic.

For example, suppose there are two processes, Process A and Process B. Each process writes several messages to the same named pipe. As they are written, some of the messages from Process A might become mixed with messages from Process B. However, an individual message cannot be interrupted by another message, since the messages are atomic. The following figure illustrates this example.

Also, note that if two processes (Process C and Process D) simultaneously read from the same named pipe, they receive messages from both Process A and Process B in order of transmission, but whether Process C or D receives a particular message might be uncertain. In the above figure, either Process C or Process D can receive message A1 or B1, if the processes read the pipe at the same time. The actual messages received by which process depend on the state of the system at the time of input. In other words, all applications that use a named pipe must establish a mutual protocol for effective cooperation.