Analysis on "REDIRECT"--based on Linux system

In bash, the syntax for redirection is denoted by ' > ' and ' < ', such as "2>&1", which means that the standard error output (file descriptor 2) is redirected (redirection) to the standard output (file descriptor 1).

　　

In addition to using file descriptors, you can use the filename as the redirect "direction", such as "ls > 1.txt", that is, the standard output of LS to redirect the results to 1.txt standard input (the shell will fork a sub-process, open 1.txt, read LS ' from the standard input) Output, and write to file 1.txt). Viewing 1.txt reproduces the results of the LS command.

Analysis on "REDIRECT"--based on Linux system