diff --git a/demboyz/io/demoreader.h b/demboyz/io/demoreader.h
index 069aaaf..3de4bb9 100644
--- a/demboyz/io/demoreader.h
+++ b/demboyz/io/demoreader.h
@@ -1,10 +1,12 @@
 
 #pragma once
 
+#include <cstdio>
+
 class IDemoWriter;
 
 namespace DemoReader
 {
-    void ProcessDem(void* inputFp, IDemoWriter* writer);
-    void ProcessJson(void* inputFp, IDemoWriter* writer);
+    void ProcessDem(std::FILE* inputFp, IDemoWriter* writer);
+    void ProcessJson(std::FILE* inputFp, IDemoWriter* writer);
 }
diff --git a/demboyz/io/demreader.cpp b/demboyz/io/demreader.cpp
index eb45ca1..8f3739a 100644
--- a/demboyz/io/demreader.cpp
+++ b/demboyz/io/demreader.cpp
@@ -139,7 +139,7 @@ PacketTrailingBits ParsePacket(uint8_t* packet, size_t length,
     return trailingBits;
 }
 
-void DemoReader::ProcessDem(void* inputFp, IDemoWriter* writer)
+void DemoReader::ProcessDem(std::FILE* inputFp, IDemoWriter* writer)
 {
     void* netDataStructs[32];
     void* demDataStructs[9];
@@ -147,7 +147,7 @@ void DemoReader::ProcessDem(void* inputFp, IDemoWriter* writer)
     CreateDemMsgStructs(demDataStructs);
 
     SourceGameContext context = SourceGameContext();
-    DemoFileReader reader(reinterpret_cast<FILE*>(inputFp));
+    DemoFileReader reader(inputFp);
     {
         demoheader_t header;
         reader.ReadDemoHeader(header);
diff --git a/demboyz/io/jsonreader.cpp b/demboyz/io/jsonreader.cpp
index 95e5450..3a329f1 100644
--- a/demboyz/io/jsonreader.cpp
+++ b/demboyz/io/jsonreader.cpp
@@ -1,6 +1,6 @@
 
 #include "demoreader.h"
 
-void DemoReader::ProcessJson(void* inputFp, IDemoWriter* writer)
+void DemoReader::ProcessJson(std::FILE* inputFp, IDemoWriter* writer)
 {
 }