calculates and prints a 16-bit checksum for the named file,
and also prints the number of 512 byte blocks in the file.
It is typically used to look for bad spots, or
to validate a file communicated over
some transmission line.
causes an alternate algorithm to be used
in computing the checksum.
language-specific message file (See LANG on
is indistinguishable from end of file on
most devices; check the block count.