bash - How can I send the stdout of one process to multiple processes using (preferably unnamed) pipes in Unix (or Windows)? -

i'd redirect stdout of process proc1 2 processes proc2 , proc3:

         proc2 -> stdout        /  proc1        \           proc3 -> stdout 

i tried

 proc1 | (proc2 & proc3) 

but doesn't seem work, i.e.

 echo 123 | (tr 1 & tr 1 b) 

writes

 b23 

to stdout instead of

 a23  b23 

<sup>editor's note:
- >(…) process substitution nonstandard shell feature of some posix-compatible shells: bash, ksh, zsh.
- written, answer accidentally sends output process substitution's output through pipeline too.
- echo 123 | tee >(tr 1 a) >(tr 1 b) >/dev/null prevent that, has pitfalls: output process subsitutions unpredictably interleaved, and, except in zsh, pipeline may terminate before commands inside >(…) do.</sup>

in unix (or on mac), use tee command:

$ echo 123 | tee >(tr 1 a)  | tr 1 b b23 a23 

usually use tee redirect output multiple files, using >(...) can redirect process. so, in general,

$ proc1 | tee >(proc2) ... >(procn-1) | procn 

will want.

under windows, don't think built-in shell has equivalent. microsoft's windows powershell has tee command though.