sum(1)
NAME
sum − sum and count blocks in a file
SYNTAX
sum file
DESCRIPTION
The sum command calculates and prints a 16-bit checksum for the named file, and also prints the number of blocks in the file. It is typically used to look for bad spots or to validate a file communicated over some transmission line.
DIAGNOSTICS
“Read error” is indistinguishable from end of file on most devices; check the block count.