diff --git a/demo/common.h b/demo/common.h
index 9d3d888..0a2f2d8 100644
--- a/demo/common.h
+++ b/demo/common.h
@@ -44,10 +44,23 @@ void write(const char *filename,
         written = fwrite(t, sizeof(unsigned char), size, out);
         fclose(out);
         if (written == 0) {
-            perror("texture write error");
+            perror("write error");
         }
     }
 }
 
 
-
+void append(const char *filename, const char *t, unsigned size) {
+    if (filename == NULL) {
+        return;
+    }
+    unsigned int written = 0;
+    FILE *out = fopen(filename, "ab");
+    if (out != NULL) {
+        written = fwrite(t, sizeof(unsigned char), size, out);
+        fclose(out);
+        if (written == 0) {
+            perror("write error");
+        }
+    }
+}
diff --git a/demo/extractmesh.c b/demo/extractmesh.c
index 2ce3c6e..62b89de 100644
--- a/demo/extractmesh.c
+++ b/demo/extractmesh.c
@@ -1,6 +1,61 @@
 #include "common.h"
 #include "devil1geo.h"
 
+void writemesh(const struct MeshHeader *mh, 
+               const struct Mesh *m, 
+               const char *filename, 
+               unsigned int i) {
+    char *fn = (char*)malloc(strlen(filename) + 3 + 4);
+    sprintf(fn, "%s_%d.msh", filename, i);
+    struct Header h = {
+        1,
+        0,
+        0,
+        0,
+        0xCCCCCCCC,
+        0
+    };
+    // mesh header offset batches need to be changed for compability with parsing.
+    struct MeshHeader newmh = *(mh);
+    newmh.offsetBatches = sizeof(struct Header) + sizeof(struct MeshHeader);
+    write(fn, (char*)(&h),         sizeof(struct Header));
+    append(fn, (char*)(&newmh),    sizeof(struct MeshHeader));
+
+
+
+    // batch data the same treatment.
+    struct BatchData * newBatches = malloc(newmh.numBatch * sizeof(struct BatchData));
+    uint64_t previousBatch = 0;
+    for (int i = 0; i < newmh.numBatch; i++) {
+      newBatches[i] = (m -> b) -> bd[i];
+      unsigned int nVertices = m -> b -> bd[i].numVertex;
+      if (previousBatch == 0) {
+        newBatches[i].offsetPositions = newmh.offsetBatches + ( newmh.numBatch * sizeof(struct BatchData));
+      }
+      else {
+        newBatches[i].offsetPositions = previousBatch;
+      }
+      newBatches[i].offsetNormals     = newBatches[i].offsetPositions   + (sizeof(struct Coordinate)  * nVertices);
+      newBatches[i].offsetUVs         = newBatches[i].offsetNormals     + (sizeof(struct Coordinate)  * nVertices);
+      newBatches[i].offsetBoneIndexes = newBatches[i].offsetUVs         + (sizeof(struct UVs)         * nVertices);
+      newBatches[i].offsetBoneWeights = newBatches[i].offsetBoneIndexes + (sizeof(struct BoneIndexes) * nVertices);
+      append(fn, (char*)(&newBatches[i]), sizeof(struct BatchData));
+      previousBatch                   = newBatches[i].offsetBoneWeights + (sizeof(struct BoneWeights) * nVertices);;
+    }
+
+    for (int i = 0; i < newmh.numBatch; i++) {
+      unsigned int nVertices = m -> b -> bd[i].numVertex;
+      append(fn, (char*)(m -> b[i].vd.positions), sizeof(struct Coordinate)  * nVertices);
+      append(fn, (char*)(m -> b[i].vd.normals),   sizeof(struct Coordinate)  * nVertices);
+      append(fn, (char*)(m -> b[i].vd.u),         sizeof(struct UVs)         * nVertices);
+      append(fn, (char*)(m -> b[i].vd.bi),        sizeof(struct BoneIndexes) * nVertices);
+      append(fn, (char*)(m -> b[i].vd.bw),        sizeof(struct BoneWeights) * nVertices);
+    }
+
+    free(newBatches);
+    free(fn);
+}
+
 void extractmeshes(const char *filedata,
                    unsigned int filesize,
                    const char *filename) {
@@ -17,7 +72,7 @@ void extractmeshes(const char *filedata,
         m.b = (struct Batch*)malloc(sizeof(struct Batch) * (mh -> numBatch));
         if (m.b != NULL) {
             DEVIL1GEO.getmesh(&m, i, filedata);
-            // do something with mesh e.g write to file.
+            writemesh(mh, &m, filename, i);
             free(m.b);
         }
     } // end for
@@ -28,8 +83,6 @@ int main(int argc, char ** argv) {
     char *f = argv[1];
     unsigned int bufsize = 0;
     char *buffer         = loadfile(f, &bufsize);
-//    unpackpld(buffer, bufsize, f);
-//    exporttextures(buffer, bufsize, f);
     extractmeshes(buffer, bufsize, f);
     free(buffer);
     return 0;
diff --git a/src/devil1geo.c b/src/devil1geo.c
index bf3cfb2..7bd72c7 100644
--- a/src/devil1geo.c
+++ b/src/devil1geo.c
@@ -113,7 +113,7 @@ static bool getmesh(struct Mesh *m,
         for (j = 0; j < mh -> numBatch; j++) {
             unsigned int offset = mh->offsetBatches + j * sizeof(struct BatchData);
             getmeshbatch(&b, offset, filedata);
-            printmeshbatch(&b);
+//            printmeshbatch(&b);
             m -> b[j] = b;
         }
         done = true;
@@ -121,3 +121,4 @@ static bool getmesh(struct Mesh *m,
     return done;
 }
 
+