[tarruda]

That doesn't seem like an efficient way to do it.

Commands that process file in place (sed -i) write to a temporary file in the same filesystem and then rename to the target file, which works if you want to process files that don't fit into memory.

[jpab]

I apologise, I was speaking loosely. I don't know if sponge collects input in memory or in a file. (Frankly I've never needed to care since the files I've ever needed this tool for have all been small)

[mslm]

Without inspecting the implementation of `sponge` that's how I assumed it already internally worked.