資料來源 : Free On-Line Dictionary of Computing
standard input/output
The predefined input/output
channels which every {Unix} process is initialised with.
Standard input is by default from the terminal, and standard
output and standard error are to the terminal. Each of these
channels (controlled via a {file descriptor} 0, 1, or 2 -
stdin, stdout, stderr) can be redirected to a file, another
device or a {pipe} connecting its process to another process.
The process is normally unaware of such {I/O redirection},
thus simplifying prototyping of combinations of commands.
The {C} programming language library includes routines to
perform basic operations on standard I/O. Examples are
"printf", allowing text to be sent to standard output, and
"scanf", allowing the program to read from standard input.
(1996-06-07)