Shell输出重定向

To redirect stderr to stdout and have error messages sent to the same file as standard output, use the following:

正确的写法：command > file 2>&1

> file redirect the stdout to file, and 2>&1 redirect the stderr to the current location of stdout.

The order of redirection is important. For example, the following example redirects only stdout to file. This happens because the stderr is redirected to stdout before the stdout was redirected to file.

错误的写法：command 2>&1 > file

Another way to redirect stderr to stdout is to use the &> construct. In Bash &> has the same meaning as 2>&1:

参考：https://linuxize.com/post/bash-redirect-stderr-stdout/