NAME

sum − print checksum and block count of a file

SYNOPSIS

sum [ −r ] [ files ]

DESCRIPTION

sum calculates and prints a 16-bit checksum for the named files, 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.  If no files are specified in the command line, the checksum will be computed on the input from stdin.  The option −r causes an alternate algorithm to be used in computing the checksum. 

EXAMPLE

sum filea

produces the checksum and the block count of "filea". 

SEE ALSO

wc(1). 

DIAGNOSTICS

"Read error" is indistinguishable from end of file on most devices; check the block count. 

Version 2.5  —  April 22, 1987