I think this behaviour is supposed to be a feature of shell. Pipelines are executed in parallel. Also, see `sponge` from `moreutils` (http://kitenet.net/~joey/

I think this behaviour is supposed to be a feature of shell. Pipelines are executed in parallel. Also, see `sponge` from `moreutils` (http://kitenet.net/~joey/code/moreutils/ http://kitenet.net/~joey/code/moreutils/): $ man sponge ... sponge reads standard input and writes it out to the specified file. Un‐like a shell redirect, sponge soaks up all its input before opening the output file. This allows constructing pipelines that read from and write to the same file.