sum - print checksum and block or byte count of file(s)
sum [-r] [-p] [file ...]
sum is obsolescent and should not be used in new applications that are
intended to be portable between systems. Use cksum instead (see
sum calculates and prints to standard output a checksum for each named
file, and also prints the size of the file in 512 byte blocks, rounded
The default algorithm is a 16-bit sum of the bytes in which overflow
is ignored. Alternate algorithms can be selected with the -r and -p
Standard input is used if no file names are given.
sum is typically used to verify data integrity when copying files
sum recognizes the following options:
-r Use an alternate algorithm in which the 16-bit sum is
right rotated with each byte in computing the checksum.
-p Use the 32-bit cyclical redundancy check (CRC)
algorithm used by cksum.
sum returns the following values upon completion:
0 All files were processed successfully.
>>>>0 One or more files could not be read or some other error
If an inaccessible file is encountered, sum continues processing any
remaining files, but the final exit status is affected.
Read error conditions are indistinguishable from end of file on most
devices; check the block or byte count.
This command is likely to be withdrawn from X/Open standards.
Hewlett-Packard Company - 1 - HP-UX Release 11i: November 2000
Applications using this command might not be portable to other
vendors' platforms. The usage of cksum(1) is recommended.
cksum(1), wc(1), pdf(4).
sum: SVID2, SVID3, XPG2, XPG3
Hewlett-Packard Company - 2 - HP-UX Release 11i: November 2000