MMAP_SZ
ret = msync(smap, MMAP_SZ, MS_SYNC);
ret = msync(smap, MMAP_SZ, MS_SYNC);
smap = mmap(0, MMAP_SZ, PROT_READ | PROT_WRITE,
ret = ftruncate(fileno(ftmp), MMAP_SZ);
smap = mmap(0, MMAP_SZ, PROT_READ | PROT_WRITE,