Shell script for generating a large number of files randomly, support multithreading / SHELL脚本使用多线程随机生成大量文件

genrateFiles.sh

#!/bin/sh
# 文件生成路径 / Directory
TMPDIR="./tmp"
# 线程数 / Thread numbers
THNUM=5 
# 文件数量 / File numbers
JOBNUM=100000 
function randStr
{
    if [[ ! -n "$1" ]]; then
        LEN=1000
    else
        LEN=$1
    fi
    j=0;
    for i in {a..z}; do
        array[$j]=$i;j=$(($j+1))
    done
    for i in {A..Z}; do
        array[$j]=$i;j=$(($j+1))
    done
    for ((i=0;i<${LEN};i++)); do 
        STRS="$STRS${array[$(($RANDOM%$j))]}"
    done
    echo ${STRS}
}
function createFile() {
    if [[ ! -n "$1" ]]; then
        FILENAME="tmpfile"
    else
        FILENAME=$1
    fi
    # 随机字符串长度  100~200
    STRLEN=($RANDOM%100+100)
    echo "creating file ${FILENAME}"
    echo `randStr $STRLEN` > ${FILENAME}
}
# 清理临时文件 / Clean tmp file
rm -rf ${TMPDIR}/`hostname`
mkdir -pv ${TMPDIR}/`hostname`
# 多线程执行任务 / Multithreading
TMPFIFO="/tmp/$$.fifo" 
mkfifo ${TMPFIFO}

exec 6<>${TMPFIFO}
for ((i=0;i<${THNUM};i++));do
    echo
done >&6 
for ((i=0;i<${JOBNUM};i++)); do
    read -u6
    {
        createFile ${TMPDIR}/`hostname`/${i}.log
    } &
    echo >&6
done

# 等待所有线程运行完毕 / Wait for job done.
wait
rm -f ${TMPFIFO}
exec 6>&-
echo "Job done!"