The finger utility is a more complex utility that gives the administrator a lot of information, with a syntax that allows for selective reporting. You can use finger to get information about local users or users on remote hosts on the network. RFC 1288, "The Finger User Information Protocol," is the most recent RFC in a series to define this protocol. The finger protocol uses TCP, port 79. The finger command opens a TCP connection with a finger server daemon on a system and sends a line of text that makes up the query. The server responds and then closes the TCP connection. The RFC goes on to define different types of queries and how they can be forwarded from one machine to another. If you think that people who write these RFCs don't have a sense of humor, ponder the following paragraph taken from RFC 1288:
Now, with a sense of humor like that, is it any wonder that they name a user information protocol "finger"? However, you should note that as the Internet continues to infiltrate almost every type of electronic appliance, there are already "snack machines" that are part of a network. Recently, beverage machines have been developed that charge a different price depending on the current temperature! The capability to inventory such machines from a remote site can greatly reduce labor costs associated with visiting each machine on a regular basis. The syntax for the finger command on Solaris is finger [ -bfhilmpqsw ] [ username ... ] finger [ -l ] [ username@hostname 1 ] [@hostname 2 ...@hostname n ... ] ] finger [ -l] [ @hostname 1 [ @hostname 2 ...@hostname n ... ] ] where
The default information displayed about each user is the username, the user's full name, the terminal type, the amount of idle time, the login time, and the hostname if the user is logged in to the system remotely. If you provide a username on the command line, more information will be displayed. When using this method, you can specify more than one username and the user does not have to be logged in to the system for finger to display information about the user. However, this is limited to just users on the machine on which you are executing the finger command. Additional information you'll see if you specify one or more usernames includes the user's home directory and login shell, the time the user logged in (or last logged in), the last time the user received any email, and the last time the user read his email. If the plain-text files .project and .plan exist in the user's home directory, their contents will be displayed. In the syntax that uses the username@hostname1 [@hostname2 ... @hostnamen] or @hostname1 [@hostname2 ...@hostnamen], the finger request is sent first to the last hostname in the list (hostnamen), which sends it to the next-most previous host in the list, until the request reaches hostname1. Note also that the username@hostname syntax allows only the -l command-line option. The FreeBSD syntax for this command is a little simpler. The syntax is finger [-lmpshoT] [user ...] [user@host ...] where
This version of finger also enables you to view information about hosts on other computers. Use the format user for users on the local machine and user@hostname for remote users. Caution The finger command is rarely used today. In fact, it's often disabled because it represents a security risk to have it running. |