bash function to prepend text to output of script (example use in here too)

label-output.sh

function label_stream()
{
  perl -sne '$|=1; print "[$cmd]\t$_"' -- -cmd="$1"
}

# example use
ls -lafh . | label_stream "ls"

# output
[ls]	drwxr-xr-x    6 nickjacob  staff   204B Nov 11  2012 Processing/
[ls]	drwxr-xr-x    6 nickjacob  staff   204B Dec  4  2012 progress/
[ls]	drwxr-xr-x    5 nickjacob  staff   170B Nov 19  2011 Projects/
[ls]	drwxr-xr-x    3 nickjacob  staff   102B Oct 24 00:10 queer_1.oo3/
[ls]	drwxr-xr-x    3 nickjacob  staff   102B Dec  8 13:10 Queer_Final.oo3/