In order to use NetLocalGroupAddMember, I need to get the SID first.

For that, I am using LookupAccountName. Here's the structure of that command.

BOOL LookupAccountName(
LPCTSTR lpszSystem, // address of string for system name
LPCTSTR lpszAccount, // address of string for account name
PSID psid, // address of security identifier
LPDWORD lpcbSid, // address of size of security identifier
LPTSTR lpszReferencedDomain, // address of string for referenced domain
LPDWORD lpcchReferencedDomain, // address of size of domain string
PSID_NAME_USE psnu // address of SID-type indicator
);

Is this DECLARE ok to define that?

DECLARE LOGICAL LookupAccountName STRING,STRING,STRING,INTEGER,STRING,INTEGER,STRING

I am not sure if PS represent a string or an integer.

Also, I am not sure about the first 2 parameters. Usually, we pass the server name and user name but here we have to pass a constant for both of those parameters.