Java兼容的cksum函数

Jacksum：http：//www.jonelo.de/java/jacksum/index.html

cksum         algorithm:   POSIX 1003.2 CRC algorithm   length:      32 bits   type:        crc   since:       Jacksum 1.0.0   comment:     - under BeOS    it is /bin/cksum     - under FreeBSD it is /usr/bin/cksum     - under HP-UX   it is /usr/bin/cksum and       /usr/bin/sum -p     - under IBM AIX it is /usr/bin/cksum     - under Linux   it is /usr/bin/cksum

它是开源的。