>I am trying to put together a VFP 5.0 app that will use Windows NT 4.0 security. How can I use VFP to first figure out what NT user is logged in to the PC and then what group(s) he/she may belong to? Once I can capture that information, I hope to then use it to determine what forms and menu options are available to that user.
>
>Any help in this area would be greatly appreciated.

There are a number of ways to get the current username; the simplest, assuming that the Windows Scripting Host has been installed:

oWshNet = CREATEOBJ('wscript.network')
? oWshNet.UserName    && login to the local station
? oWshNet.DomainName  && login to the current domain

If the WSH is not available, you'll need to use the WNetGetUser() API call.  It's fairly simple to use, and prototypes in VFP as:

DECLARE INTEGER WNetGetUser IN Win32API ;
   STRING lpResourceName, ;
   STRING lpUserName, ;
   INTEGER @lpUserNameLen

cUserName = REPL(CHR(0),256)
nNameLen = 256
IF  WNetGetUser('\\MyServer\SomeShare',@cUsername, @nNameLen) = 0
   *  The first nNameLen-1 characters of cUserName now contain
   *  the name of the user accessing the resource \\MyServer\SomeShare
   *  which well might not be the WIndows Login name
ELSE
   *  Something broke
ENDIF

Determining the group membership requires the use of the NetUserGetGroups() API call. Manipulating the result really requires the use of a wrapper .DLL, since the memory used as a buffer to return the group structures needs to remain static and be relesed with NetAPIBufferFree() afterwards. You probably only need the data contained in a GROUP_USERS_INFO_0 structure, which is easier to parse. You need to pass the name of the server whose groups are to be considered; passing a null for the servername resolves only local groups.