Looking Up a User's Full Name

Computers running Windows NT can be organized into a domain, which is a collection of computers on a Windows NT Server network. The domain administrator maintains centralized user and group account information.

To find the full name of a user, given the user name and domain name on Windows NT:

• Convert the user name and domain name to Unicode, if they are not already Unicode strings.
• Look up the computer name of the domain controller (DC) by calling NetGetDCName.
• Look up the user name on the DC computer by calling NetUserGetInfo.
• Convert the full user name to ANSI, unless the program is expecting to work with Unicode strings.

The following sample code is a function that takes a user name and a domain name in the first two arguments and returns the user's full name in the third argument.

#include <windows.h>
#include <lm.h>
#include <stdio.h>

BOOL GetFullName( char *UserName, char *Domain, char *dest )
{
    WCHAR wszUserName[256];          // Unicode user name
    WCHAR wszDomain[256]; 
    LPBYTE ComputerName;

    struct _SERVER_INFO_100 *si100;  // Server structure
    struct _USER_INFO_2 *ui;         // User structure

// Convert ANSI user name and domain to Unicode

    MultiByteToWideChar( CP_ACP, 0, UserName,
        strlen(UserName)+1, wszUserName,                          sizeof(wszUserName)/sizeof(wszUserName[0]) );
    MultiByteTOWideChar( CP_ACP, 0, Domain,
        strlen(Domain)+1, wszDomain, sizeof(wszDomain)/sizeof(wszDomain[0]) );

// Get the computer name of a DC for the domain.

    NetGetDCName( NULL, wszDomain, &ComputerName );

// Look up the user on the DC.

    if( NetUserGetInfo( (LPWSTR) ComputerName,
        (LPWSTR) &wszUserName, 2, (LPBYTE *) &ui ) )
    {
        printf( "Error getting user information.\n" );
        return( FALSE );
    }

// Convert the Unicode full name to ANSI.

    WideCharToMultiByte( CP_ACP, 0, ui->usri2_full_name, -1,
        dest, 256, NULL, NULL );

    return (TRUE);
}