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SunOS man pages : sum (1)

User Commands                                              sum(1)

NAME

sum - print checksum and block count for a file

SYNOPSIS

sum [ -r ] [ file ... ]

DESCRIPTION

The sum utility calculates and prints a 16-bit checksum for the named file and 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.

OPTIONS

The following options are supported: -r Use an alternate (machine-dependent) algorithm in com- puting the checksum.

OPERANDS

The following operands are supported: file A path name of a file. If no files are named, the standard input is used.

USAGE

See largefile(5) for the description of the behavior of sum when encountering files greater than or equal to 2 Gbyte ( 2 **31 bytes).

ENVIRONMENT VARIABLES

See environ(5) for descriptions of the following environment variables that affect the execution of sum: LC_CTYPE, LC_MESSAGES, and NLSPATH.

EXIT STATUS

The following exit values are returned. 0 Successful completion. >0 An error occurred.

ATTRIBUTES

See attributes(5) for descriptions of the following attri- butes: SunOS 5.8 Last change: 7 Nov 1995 1 User Commands sum(1) ____________________________________________________________ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | | Availability | SUNWesu | | CSI | enabled | |_____________________________|_____________________________|

SEE ALSO

cksum(1), sum(1B), wc(1), attributes(5), environ(5), largefile(5)

DIAGNOSTICS

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

NOTES

Portable applications should use cksum(1). sum and usr/ucb/sum (see sum(1B)) return different check- sums. SunOS 5.8 Last change: 7 Nov 1995 2