get stdout to variable and stdout at sametime

{ var="$( ls / | tee >(cat - >&2) )"; } 2>&1; echo -e "*** var=$var"
Sometimes you want to write the script output to stdout but you need to send it to email. If you use: var="$( ls / )"; echo -e "$var"; works but, you need to wait the script terminate to bufferize then print the output var; With this way, you can use/work/print the output before the variable receive all the output content, then after it you can use the variable for anything else, like send email.
Sample Output
bin
boot
lib
...
*** var=[bin
boot
lib
...]

2
2010-11-19 19:36:39

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