Save all cookies from first page in text file on hard disk

I need to sa开发者_如何学JAVAve all cookies from first page in text file on hard disk.

How to do this with javascript?

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For security reasons you cannot use javascript to read/write files on the client computer. You can read/write cookies which could be persistent and if they are persistent they are actually stored by the browser on the client computer but the way and location this is done is out of your control.