Constrain constant values to a single location in code

src/script/standard.cpp

@@ -16,6 +16,7 @@ using namespace std;
 
 typedef vector<unsigned char> valtype;
 
+bool fAcceptDatacarrier = true;
 unsigned nMaxDatacarrierBytes = MAX_OP_RETURN_RELAY;
 
 CScriptID::CScriptID(const CScript& in) : uint160(Hash160(in.begin(), in.end())) {}

src/script/standard.h

@@ -26,6 +26,7 @@ public:
 };
 
 static const unsigned int MAX_OP_RETURN_RELAY = 83; //! bytes (+1 for OP_RETURN, +2 for the pushdata opcodes)
+extern bool fAcceptDatacarrier;
 extern unsigned nMaxDatacarrierBytes;
 
 /**