$ split -b 1G -a 3 -d test.dat test.dat.
  • "-b"は、分割のサイズ
  • "-a"は、接尾句の長さ(3なら"000"とか"aaa")
  • "-d"は、接尾句を数字にしてくれる(00〜、指定無だと英字)
  • 最後に、分割対象のファイル名と、分割後に出力されるファイルの接頭句を指定

上記例だと、test.dat.000, test.dat.001 〜 1GBに分割されたファイルが連番で出力される。


$ cat test.dat.* > test.dat



$ split --help
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   generate suffixes of length N (default 2)
      --additional-suffix=SUFFIX  append an additional SUFFIX to file names.
  -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[=FROM]  use numeric suffixes instead of alphabetic.
                                   FROM changes the start value (default 0).
  -e, --elide-empty-files  do not generate empty output files with '-n'
      --filter=COMMAND    write to shell COMMAND; file name is $FILE
  -l, --lines=NUMBER      put NUMBER lines per output file
  -n, --number=CHUNKS     generate CHUNKS output files.  See below
  -u, --unbuffered        immediately copy input to output with '-n r/...'
      --verbose           print a diagnostic just before each
                            output file is opened
      --help     display this help and exit
      --version  output version information and exit

SIZE is an integer and optional unit (example: 10M is 10*1024*1024).  Units
are K, M, G, T, P, E, Z, Y (powers of 1024) or KB, MB, ... (powers of 1000).

CHUNKS may be:
N       split into N files based on size of input
K/N     output Kth of N to stdout
l/N     split into N files without splitting lines
l/K/N   output Kth of N to stdout without splitting lines
r/N     like 'l' but use round robin distribution
r/K/N   likewise but only output Kth of N to stdout

Report split bugs to
GNU coreutils home page: <>
General help using GNU software: <>
Report split translation bugs to <>
For complete documentation, run: info coreutils 'split invocation'