After the installation, I try to run docsify. However, there's an error saying /usr/bin/env: ‘node\r’: No such file or directory.
Finally, I found the solution to the problem.
Just to use dos2unix to convert /use/local/lib/node_modules/docsify-cli/bin/docsify to Unix format.
Maybe it is the format(dos) of the file that cause the problem.