The ac command is a utility for displaying statistics about user activity on a Linux system. It reads data from the system’s accounting files and displays a summary of information about users’ login and logout times, the amount of time they spent logged in, and the number of processes they ran.
You can also use the -f option to specify the name of the accounting file to read data from. By default, ac reads data from the system’s default accounting file, which is usually located at /var/account/pacct.
For more information about the ac command and a complete list of options, you can refer to the man page by typing “man ac” at the command prompt.
ac Command Examples
1. Print how long the current user has been connected in hours:
# ac
2. Print how long users have been connected in hours:
# ac --individual-totals
3. Print how long a particular user has been connected in hours:
# ac --individual-totals {{username}}
4. Print how long a particular user has been connected in hours per day (with total):
# ac --daily-totals --individual-totals {{username}}
5. Also display additional details:
# ac --compatibility