[YLUG] How do to substition in a file with sed or similar

[Robert Hulme]

Hi list,

I know I can:
sed s/foo/bar/ myfile

which dumps to stdout

How I do the substition on the file 'in place'?

sed s/foo/bar/ myfile > myfile

Results in a zero length file (which I'd kinda expect from the stream editor).

Do I need to use a temporary file or is there some kind of buffer I could use:
sed s/foo/bar/ myfile | streambuffer > myfile

Or is there a magic switch or should I be using something other than sed?

Thanks muchly,
-Rob

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