What Is Finger in Linux?

Linux includes many commands and utilities like finger whose purpose might not be readily apparent to most users. If you are a desktop Linux user who is not part of a larger local or wide area network, you may never need to run the finger command. For Linux system administrators, however, finger is a important tool to keep tabs on who has access to their network.

Finger was a operating system administration command written by Stanford University computer scientist Les Earnest in 1971. It was created as a tool to gather information about users with university network system access. Finger became the official, international networking protocol RFC 742 in 1977. Eventually, finger became a terminal command included with UNIX and Linux operating systems.

The Linux finger command can provide a user's full name, login name, terminal name, elapsed time since login, command shell preference, phone number, email address and whether or not they have email on the system's mail server. If you wanted basic information a about a user named "allenb" you would launch your Linux terminal and execute a command like the following:

finger allenb

If you want to avoid the Linux command prompt altogether, you can run a graphical user interface version of finger. The Gnome Nettools app features finger along with other network commands like ping, netstat, lookup and whois. To get information about a user with Nettools, you click the tab for finger, type a username in the input box and then click the "Finger" button.

Finger may be considered the first Internet blogging tool. Initially, users would create a hidden, plain-text file called .plan that would contain information about their whereabouts, work schedule or office hours. If a user had a .plan file in his Home directory, it would print along with the rest of their user information whenever they were fingered. Eventually users began to use their .plan files to talk about after work activities or express their personal opinions about work and life in general. Today, Linux users can also create .project files that tell about the work they were doing, .forward files which forward their system emails to other mail servers and .pgpkey files that contain their public Pretty Good Privacy encryption key.