LTB 1.7. Input and Output

The UNIX I/O scheme is based on two dazzlingly simple ideas.
First, UNIX file I/O takes the form of arbitrarily long sequences of characters (bytes). In contrast, file systems of older vintage have more complicated I/O schemes (e.g., "block,""record,""card image," etc.).
Second, everything on the system that produces or accepts data is treated as a file; this includes hardware devices like disk drives and terminals.

1.7.1. Standard I/O

1.7.2. I/O Redirection

1.7.3. Pipelines