Early support for larger-than-512-byte sectors and even earlier support
for sgdisk program. (The latter is just proof-of-concept at this point;
it doesn't do anything useful.)
diff --git a/support.h b/support.h
index e414df0..b261b76 100644
--- a/support.h
+++ b/support.h
@@ -68,6 +68,8 @@
 void ReverseBytes(void* theValue, int numBytes); // Reverses byte-order of theValue
 uint64_t PowerOf2(int value);
 int OpenForWrite(char* deviceFilename);
+int myRead(int fd, char* buffer, int numBytes);
+int myWrite(int fd, char* buffer, int numBytes);
 void DiskSync(int fd); // resync disk caches to use new partitions
 
 uint64_t disksize(int fd, int* err);