Special filenames

/dev/null

This is a special file, not a directory. It accepts and discards all input written to it and reports that the write operation succeeded. It provides an end-of-file indication when read from.

/dev/stdin

This is a duplicate of file descriptor zero, which is the standard input device (usually the keyboard).

/dev/stdout

This is a duplicate of file descriptor one, which is the standard output device (usually the screen).

/dev/stderr

This is a duplicate of file descriptor two, which is the standard error device (usually the screen).

/dev/fd/number

This is a duplicate of file descriptor number:

• /dev/fd/0 is the same as /dev/stdin
• /dev/fd/1 is the same as /dev/stdout
• /dev/fd/2 is the same as /dev/stderr

Further information

• man fd

2021-12-18