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I want to be able to split an output from a command line that goes into a file. I want either or both of the following ways to split:

  • Split based on file size. If it gets to say 500kb, then create a new file
  • Split based on lines in file. If it gets to 1000 lines, then create a new file

Of course, this also means I need a variable name for the output

This is the command I'm running now:

java -jar "C:\Processors\myProcessor.jar" >> "C:\Processors\myprocessor.log"

Would like 'myprocessor.log' to be split in files accordingly.

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The split command does exactly what you're after, with options to split on file size or on line count. From the man page:

split - split a file into pieces

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.


-b, --bytes=SIZE put SIZE bytes per output file

-l, --lines=NUMBER put NUMBER lines per output file

You can get the split command in the GnuWin32 CoreUtils package for use on a Windows machine.

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If you want to do this without modifying myProcessor.jar, then you'll need to post-process the log file. I suspect you could do this within Powershell but it is not immediately apparent to me how. There is nothing in Windows to do this.

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i believe what you're trying to do requires writing a script at least (command line only won't help)

for scripting purposes of such i would recommend writing a Ruby script (Ruby is a very powerful and extremely easy to learn language - very friendly). writing a batch file to do it will eat your brains (at least it would mine)

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yeah... but I see no other way. I would have to rewrite all the code. – elcool Feb 17 '11 at 12:47

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