Shell并发编程Demo

#!/bin/bash_sleep_A(){    sleep 3s}_sleep_B(){    sleep 2s}_sleep_C(){    sleep 1s}_sleep_D(){    sleep 2s}_sleep_E(){    sleep 3s}_sleep_F(){    sleep 3s}_sleep_G(){    sleep 1s}# create fifo[[ -e temp.FIFO ]] && rm -f temp.FIFOmkfifo temp.FIFO# set file descreptor 6 to FIFO file "temp.FIFO"# open file temp.FIFO for fd6 I/Oexec 6<>temp.FIFO# multi-thread=3echo >&6echo >&6echo >&6for one in {A..G}do    read -u6    {        echo "${one}${one}${one} begins."        _sleep_${one}        echo "${one}${one}${one} done."        echo >&6    }&donewaitexec 6>&-rm temp.FIFOecho ""echo "ALL HAVE DONE."echo ""