"Shell" establishes a script to count the number of currently logged on users

Who command

The WHO command is to display the user information of the current login system, execute the WHO command to know which users are currently logged into the system, execute the WHO command separately to list the login account, the terminal to use, the time to log in, and from where to log in or use which monitor.

Counting the number of users is based on the WHO command, the WHO command to draw the list count, we can use the WC (Word count) program, it can calculate the number of travel (line), Word and character (character), in this case, we use wc–l, that is, only the number of travel:

| (pipe) symbol can be established between two programs (pipeline) who's output, as a WC input, the result of the WC is the number of users logged

This counts the number of users only to execute the above n_users.sh script.

"Shell" establishes a script to count the number of currently logged on users