Linux shell模拟多线程拷贝

#!/bin/sh
#日志文件
log_file=/data/threadcp.log

a=$(date +%H%M%S)
echo -e "startTime:\t$a"

#最大线程数
nParellel=

#获取需拷贝文件数组
cd /data/testsrc
filelist=()
j=
for file in $(ls *)
do
    filelist[j]=$file
    let "j++"
done

#获取拷贝文件数
filenum=$(ls |wc -w)

aJobs=()

for ((nextJob = ; nextJob < filenum; )); do
    for ((iJob = ; iJob < nParellel; ++iJob)); do
        if [ $nextJob -eq $filenum ]; then
            break;
        fi
        if [ ! "${aJobs[iJob]}" ] || ! kill - ${aJobs[iJob]} > /dev/null; then
            {
                cp ${filelist[nextJob]} /data/extd
                echo "[$(date "+%F %T")]: ${filelist[nextJob]}" >> $log_file
#                echo "[$(date "+%F %T")]: ${nextJob}" >> $log_file
            } &
            let "nextJob++"
            aJobs[iJob]=$!
        fi
    done

    sleep .

done

wait
b=$(date +%H%M%S)
echo -e "endTime:\t$b"