gistfile1.diff

+		public static Group [] getgrouplist (string username)
+		{
+			// Syscall to getpwnam to retrieve user uid
+			Passwd pw = Syscall.getpwnam (username);
+			if (pw == null) 
+				return new Group [0];
+			// initialising the lngroups by 1 to get the group count
+			int ngroups = 1;
+			// allocating buffer to store group uid's
+			uint [] groups = new uint [ngroups];
+			int res = sys_getgrouplist (username, pw.pw_gid, groups, ref ngroups);
+			if (res == -1) {
+				// using value ngroups to resize buffer.
+				Array.Resize(ref groups, ngroups);
+				res = sys_getgrouplist (username, pw.pw_gid, groups, ref ngroups);
+				if (res == -1) 
+					return new Group [0];
+			}
 
+			Group [] result = new Group [ngroups];
+			for (int i = 0; i < res; i++) 
+				result [i] = Syscall.getgrgid (groups [i]);
+			return result;
+		}