Subprocess without job control spew

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# If you don't want to have [3] and [3]+ Done and all that stuff:

 ( (do_some_work_here; do_some_more)& )

# or

( just_do_some_work arg arg arg & )

# E.g. from bithon.
# Write to a fd (which is a named pipe) all of the arguments
# to the function then write a special end of stream statement.
# Do all this in the background (to avoid pipe deadlock) and 
# launch from a subshell to avoid job control spew. Remember
# fork on Linux (or Mac OS) is < 1000 cycles... i.e. less than
# one millionth of a second, so don't worry too much about this
# approach from a performance point of view (though subshells 
# are actually quite a bit more expensive).

 ( (echo "$@" >&3; echo 'print "\nbithon-eos"' >&3)& )

 # Putting the background process in a subshell removes the job control spew.

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