diff --git a/umdiff/compare.c b/umdiff/compare.c
index dbdd0dd..ad6da6d 100644
--- a/umdiff/compare.c
+++ b/umdiff/compare.c
@@ -86,12 +86,11 @@ _impl_umdiff_deltaJobSource(rs_job_t *job, rs_buffers_t *buf, void *fd_)
 }
 
 
-umdiff_File *
-umdiff_File_fromCompare(int source_fd, int target_fd)
+int
+umdiff_File_fromCompare(umdiff_File *file, int source_fd, int target_fd)
 {
     _impl_umdiff_OpaqueFd source_fd_ = { .fd = source_fd };
     _impl_umdiff_OpaqueFd target_fd_ = { .fd = target_fd };
-    umdiff_File *resultFile;
 
     rs_job_t *sigJob, *deltaJob;
     rs_buffers_t buffers = {
@@ -115,9 +114,9 @@ umdiff_File_fromCompare(int source_fd, int target_fd)
                 _impl_umdiff_sigJobSink,    workSignatures);
     rs_job_drive(deltaJob, &buffers,
                 _impl_umdiff_deltaJobSource, target_fd_.opaque,
-                _impl_umdiff_deltaJobSink,   resultFile);
+                _impl_umdiff_deltaJobSink,   file);
 
-    return resultFile;
+    return 0;
 }
 
 // vim: ft=c.doxygen
diff --git a/umdiff/compare.h b/umdiff/compare.h
index d96e0bb..5986889 100644
--- a/umdiff/compare.h
+++ b/umdiff/compare.h
@@ -21,8 +21,8 @@
  * This is the optimum approach, as it includes our optimum parameters,
  * ensuring computed blocks line up with ISO9660 sectors.
  */
-umdiff_File *
-umdiff_File_fromCompare(int source_fd, int target_fd);
+int
+umdiff_File_fromCompare(umdiff_File *file, int source_fd, int target_fd);
 
 #endif //__COMPARE_H
 
diff --git a/umdiff/main.c b/umdiff/main.c
index 97f33b4..5668bdc 100644
--- a/umdiff/main.c
+++ b/umdiff/main.c
@@ -19,21 +19,20 @@ int
 umdiff_delta(char *source, char *target, char *output)
 {
     int source_fd, target_fd, output_fd;
-    umdiff_File *result = malloc(sizeof(umdiff_File));
+    umdiff_File result;
 
     source_fd = open(source, O_RDONLY);
     target_fd = open(target, O_RDONLY);
 
-    result = umdiff_File_fromCompare(source_fd, target_fd);
+    umdiff_File_fromCompare(&result, source_fd, target_fd);
 
     output_fd = open(output, O_WRONLY|O_CREAT|O_TRUNC, 0644);
-    return umdiff_File_write(result, output_fd);
+    return umdiff_File_write(&result, output_fd);
 }
 
 int
 umdiff_patch(char *source, char *umdiff, char *output)
 {
-
     return 1;
 }