int isamd_alloc_block (ISAMD is, int cat);
void isamd_release_block (ISAMD is, int cat, int pos);
int isamd_read_block (ISAMD is, int cat, int pos, char *dst);
int isamd_write_block (ISAMD is, int cat, int pos, char *src);
int isamd_alloc_block (ISAMD is, int cat);
void isamd_release_block (ISAMD is, int cat, int pos);
int isamd_read_block (ISAMD is, int cat, int pos, char *dst);
int isamd_write_block (ISAMD is, int cat, int pos, char *src);