GNU Core Utils](http://www.gnu.org/software/coreutils/)包(可在windows下使用[这里](http://gnuwin32.sourceforge.net/packages/coreutils.htm))包含了Split工具。它对我来说很好用 :-)
–help 文档如下:
Usage: split [OPTION] [INPUT [PREFIX]]
Output fixed-size pieces of INPUT to PREFIXaa, PREFIXab, ...; default
size is 1000 lines, and default PREFIX is `x'. With no INPUT, or when INPUT
is -, read standard input.
Mandatory arguments to long options are mandatory for short options too.
-a, --suffix-length=N use suffixes of length N (default 2)
-b, --bytes=SIZE put SIZE bytes per output file
-C, --line-bytes=SIZE put at most SIZE bytes of lines per output file
-d, --numeric-suffixes use numeric suffixes instead of alphabetic
-l, --lines=NUMBER put NUMBER lines per output file
--verbose print a diagnostic to standard error just
before each output file is opened
--help display this help and exit
--version output version information and exit
SIZE may have a multiplier suffix: b for 512, k for 1K, m for 1 Meg.
例如,要把 input.txt 分割成 100Mb 的大块,只在行的两端进行分割,
split input.txt -C 100m
会给你一个名为 xaa, xab, xac 等的输出文件。