Index: src/sqlite.h.in
==================================================================
--- src/sqlite.h.in
+++ src/sqlite.h.in
@@ -2625,12 +2625,14 @@
 **
 ** These are utility routines, useful to VFS implementations, that check
 ** to see if a database file was a URI that contained a specific query 
 ** parameter, and if so obtains the value of that query parameter.
 **
-** If F is the filename pointer passed into the xOpen() method of a VFS
-** implementation and P is the name of the query parameter, then
+** If F is the database filename pointer passed into the xOpen() method of 
+** a VFS implementation when the flags parameter to xOpen() has one or 
+** more of the [SQLITE_OPEN_URI] or [SQLITE_OPEN_MAIN_DB] bits set and
+** P is the name of the query parameter, then
 ** sqlite3_uri_parameter(F,P) returns the value of the P
 ** parameter if it exists or a NULL pointer if P does not appear as a 
 ** query parameter on F.  If P is a query parameter of F
 ** has no explicit value, then sqlite3_uri_parameter(F,P) returns
 ** a pointer to an empty string.
@@ -2646,12 +2648,13 @@
 ** exist.  If the value of P is something other than an integer, then
 ** zero is returned.
 ** 
 ** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
 ** sqlite3_uri_boolean(F,P,B) returns B.  If F is not a NULL pointer and
-** is not a pathname pointer that SQLite passed into the xOpen VFS method,
-** then the behavior of this routine is undefined and probably undesirable.
+** is not a databaes file pathname pointer that SQLite passed into the xOpen
+** VFS method, then the behavior of this routine is undefined and probably
+** undesirable.
 */
 const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam);
 int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault);
 sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64);