Standard input and output files in Linux

Unix/Linux/BSD all have three special files, respectively. 1) the standard input is STDIN. in/dev/stdin, it generally refers to the keyboard input, and the shell code is 02) standard output STDOUT, in/dev/stdout, usually refers to the terminal (terminal), is the display, sh...

Unix, Linux, and BSD have three special files, respectively.

1) the standard input is STDIN. in/dev/stdin, it generally refers to the keyboard input. the code in shell is 0.

2) STDOUT of the standard output, in/dev/stdout, usually refers to the terminal (terminal), which is the display, and the code in shell is 1

3) STDERR is a standard error. in/dev/stderr, it also refers to the terminal (terminal). The difference is that the error message is sent here. the shell code is 2.

From: YEYUANGEN's column