Editing Standard streams (section)

==Standard output (stdout)==<!-- This section is linked from [[COMMAND.COM]] -->
Standard output is a stream to which a program writes its output data.  The program requests data transfer with the ''write'' operation.  Not all programs generate output.  For example, the ''[[rename (computing)|file rename]]'' command (variously called ''[[mv (Unix)|mv]]'', ''[[move (command)|move]]'', or ''[[ren (command)|ren]]'') is silent on success.

Unless [[Redirection (computing)|redirected]], standard output is inherited from the parent process.  In the case of an interactive shell, that is usually the [[text terminal]] which initiated the program.

The [[file descriptor]] for standard output is 1 (one); the [[POSIX]] <code><unistd.h></code> definition is <code>STDOUT_FILENO</code>; the corresponding C <code><stdio.h></code> variable is <code>FILE* stdout</code>; similarly, the C++ <code><iostream></code> variable is <code>std::cout</code>.