Real-Time Embedded Systems

Chapter 20

Intertask Communication

Pipe

Abstract

Similarly to message queues, pipes offer another mechanism for intertask communication. An unnamed pipe is typically used between processes that are related by either a parent-child relationship or a sibling relationship. A named pipe is a persistent file object, which is typically used between processes that are not necessarily related. Each pipe has two ends, one for writing and one for reading. The read operation on a pipe can be blocked if the pipe is empty, and the write operation on a pipe can be blocked if the available space is not sufficient to hold the data to be written. In a POSIX-compliant operating system implementation, the write operation on a pipe is atomic when the data to ...