diff --git a/demo/extractmesh.c b/demo/extractmesh.c
index ba49f9b..d15dde7 100644
--- a/demo/extractmesh.c
+++ b/demo/extractmesh.c
@@ -60,7 +60,7 @@ void extractmeshes(const char *filedata,
                    const char *filename,
                    unsigned int filesize) {
     struct Header *h = NULL;
-    if (!(DEVIL1GEO.getheader(h, filedata))|| filesize <= 0) {
+    if (!(DEVIL1GEO.getheader(&h, filedata))|| filesize <= 0) {
         return;
     }
     struct MeshHeader *mh = NULL;
diff --git a/demo/extracttexture.c b/demo/extracttexture.c
index 839ad84..8a187c3 100644
--- a/demo/extracttexture.c
+++ b/demo/extracttexture.c
@@ -8,7 +8,7 @@ void extracttextures(const char *filedata,
     struct Texture *t     = NULL;
     struct TextureBatchDescriptor *d = NULL;
     char * fmt            = NULL;
-    if (!(DEVIL1TEX.getheader(p, filedata)) || filesize == 0) {
+    if (!(DEVIL1TEX.getheader(&p, filedata)) || filesize == 0) {
         return;
     }
     fmt = (char*)malloc(strlen(filename) + 3 + 4);
diff --git a/include/devil1geo.h b/include/devil1geo.h
index 6d08f1e..7293041 100644
--- a/include/devil1geo.h
+++ b/include/devil1geo.h
@@ -86,7 +86,7 @@ typedef struct {
     void (* const printcoordinate)(struct Coordinate*, unsigned int);
 
 // input: pointer to struct, file data
-    bool (* const getheader)      (struct Header*, const char*);
+    bool (* const getheader)      (struct Header**, const char*);
 
 // input: pointer of pointer to struct, order, file data
 // ** = 'pass by reference' of a pointer to struct
diff --git a/include/devil1tex.h b/include/devil1tex.h
index b002a0a..f45be35 100644
--- a/include/devil1tex.h
+++ b/include/devil1tex.h
@@ -46,7 +46,7 @@ typedef struct {
     void (* const printbatchdesc)(struct TextureBatchDescriptor*);
 
 // input: pointer to struct, file data
-    bool (* const getheader)     (struct TexturePack*, const char*);
+    bool (* const getheader)     (struct TexturePack**, const char*);
 
 // input: pointer of pointer to struct, order, file data, file size
 // ** = 'pass by reference' of a pointer to struct
diff --git a/src/devil1geo.c b/src/devil1geo.c
index 70f5bd8..72357af 100644
--- a/src/devil1geo.c
+++ b/src/devil1geo.c
@@ -9,7 +9,7 @@ static void printmeshbatch(struct Batch*);
 
 static void printcoordinate(struct Coordinate*, unsigned int);
 
-static bool getgheader(struct Header*, const char*);
+static bool getgheader(struct Header**, const char*);
 
 static bool getmeshheader(struct MeshHeader**, unsigned int i, const char * const);
 
@@ -76,11 +76,11 @@ static void printcoordinate(struct Coordinate *p, unsigned int count) {
     }
 }
 
-static bool getgheader(struct Header* h, const char* filedata) {
+static bool getgheader(struct Header** h, const char* filedata) {
     if (filedata == NULL) {
         return false;
     }
-    h = (struct Header*)filedata;
+    (*h) = (struct Header*)filedata;
     return true;
 }
 
@@ -89,7 +89,7 @@ static bool getmeshheader(struct MeshHeader **hs,
                    const char * const filedata) {
     bool done        = false;
     struct Header *h = NULL;
-    if (hs == NULL || !(getgheader(h, filedata))) {
+    if (hs == NULL || !(getgheader(&h, filedata))) {
         return done;
     }
     if (h -> numMesh < i) {
diff --git a/src/devil1tex.c b/src/devil1tex.c
index 92bc717..f284cd8 100644
--- a/src/devil1tex.c
+++ b/src/devil1tex.c
@@ -9,7 +9,7 @@ static void printtph(struct TexturePack*);
 static void printtbd(struct TextureBatchDescriptor*);
 
 // Get Texture Pack Header
-static inline bool getpackheader(struct TexturePack*, const char*);
+static inline bool getpackheader(struct TexturePack**, const char*);
 
 // Get Texture Batch Descriptor.
 static bool gettexdescriptor(struct TextureBatchDescriptor**,
@@ -58,11 +58,11 @@ static void printtbd(struct TextureBatchDescriptor *bd) {
     }
 }
 
-inline static bool getpackheader(struct TexturePack* p, const char *filedata) {
+inline static bool getpackheader(struct TexturePack** p, const char *filedata) {
     if (filedata == NULL) {
         return false;
     }
-    p = (struct TexturePack*)filedata;
+    (*p) = (struct TexturePack*)filedata;
     return true;
 }
 
@@ -86,7 +86,7 @@ static bool gettexbatch(struct TextureBatch **batch,
                  const char *filedata,
                  unsigned int filesize) {
     struct TexturePack *p = NULL;
-    if (!(getpackheader(p, filedata))) {
+    if (!(getpackheader(&p, filedata))) {
         return false;
     }
     if (i > p -> batchNumber) {  // no such batch in texture pack