How can I find out the last time a user logged on from C++?

Raymond Chen

The PowerShell Get-LocalUser cmdlet gives you information about a local user, including the last logon time.

PS> Get-LocalUser Fred | Format-List

AccountExpires         :
Description            :
Enabled                : True
FullName               :
PasswordChangeableDate : 04/02/2023 2:25:04 PM
PasswordExpires        :
UserMayChangePassword  : True
PasswordRequired       : False
PasswordLastSet        : 04/01/2023 2:25:04 PM
LastLogon              : 04/01/2023 2:28:41 PM
Name                   : Fred
SID                    : S-1-5-21-162119347-98882960-612995125-1001
PrincipalSource        : Local
ObjectClass            : User

How can you get this information from C++?

For historical reasons, commands for operating with local users are in the LAN Manager API family. That’s because MS-DOS was a single-user operating system, so the only time you had to worry about “users” was if you were operating over the network.

This is also why a bunch of user management operations are handled by NET.EXE. The NET.EXE program was the part of LAN Manager that gave you access to all the network magic stuff.

C:\> NET USER Fred

User name                    Fred
Full Name
Comment
User's comment
Country/region code          000 (System Default)
Account active               Yes
Account expires              Never

Password last set            04/01/2023 2:25:04 PM
Password expires             Never
Password changeable          04/02/2023 2:25:04 PM
Password required            No
User may change password     Yes

Workstations allowed         All
Logon script
User profile
Home directory
Last logon                   04/01/2023 2:28:41 PM

Logon hours allowed          All

Local Group Memberships      *Administrators
Global Group memberships     *None
The command completed successfully.

The native function for getting this information is NetUserGetInfo. In particular, asking for information level 2 gives you a USER_INFO_2 structure which contains, among other things, usri2_last_logon.

The documentation includes a sample program showing how to request various levels of information and then print the results, so I won’t bother repeating it here.