June 2005
Intermediate to advanced
960 pages
23h 41m
English
book
Advanced Programming in the UNIX® Environment: Second Edition
by W. Richard Stevens, Stephen A. Rago
Content preview from Advanced Programming in the UNIX® Environment: Second EditionBecome an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
Start your free trial
Chapter 14. Advanced I/O
Introduction
This chapter covers numerous topics and functions that we lump under the term advanced I/O: nonblocking I/O, record locking, System V STREAMS, I/O multiplexing (the select and poll functions), the readv and writev functions, and memory-mapped I/O (mmap). We need to cover these topics before describing interprocess communication in Chapter 15, Chapter 17, and many of the examples in later chapters.
Nonblocking I/O
In Section 10.5, we said that the system calls are divided into two categories: the “slow” ones and all the others. The slow system calls are those that can block forever. They include
Reads that can block the caller forever if data isn’t present with certain file types (pipes, terminal devices, and network ...