diff --git a/acn/pdu.cpp b/acn/pdu.cpp
index 1046f47..cb67b7c 100644
--- a/acn/pdu.cpp
+++ b/acn/pdu.cpp
@@ -36,10 +36,10 @@ namespace PDU {
 Pdu::Pdu(Stream stream, size_t vector_size)
   : flags_(stream->peek())
 {
-  header_  = 0;
-  data_    = 0;
-  parent_  = 0;
-  inherit_ = 0; // pointer to previous PDU in block
+  header_  = nullptr;
+  data_    = nullptr;
+  parent_  = nullptr;
+  inherit_ = nullptr; // pointer to previous PDU in block
 
   // read length and vector off of the stream
   // abort if the remaining PDU length isn't available
@@ -99,7 +99,7 @@ const uint32_t Pdu::vector()
 {
   if (flags_.hasVector)
     return vector_;
-  if (inherit_ != nullptr)
+  if (inherit_)
     return inherit_->vector();
   return 0;
 }
@@ -113,9 +113,9 @@ pdu_header * Pdu::header()
 {
   if (flags_.hasHeader)
     return header_;
-  if (inherit_ != nullptr)
+  if (inherit_)
     return inherit_->header();
-  return 0;
+  return nullptr;
 }
 
 
@@ -127,9 +127,9 @@ pdu_data * Pdu::data()
 {
   if (flags_.hasData)
     return data_;
-  if (inherit_ != nullptr)
+  if (inherit_)
     return inherit_->data();
-  return 0;
+  return nullptr;
 }