具体需求：

写一个脚本，产生一个phonenum.txt文件，随机产生以139开头的手机号1000个，每个一行。

① 思路

1. 产生1000个电话号码，脚本需要循环1000次 FOR WHILE UNTIL
2. 139+8位,后8位随机产生，可以让每一位数字都随机产生 echo $[$RANDOM%10]
3. 将随机产生的数字分别保存到变量里，然后加上139保存到文件里

② 落地实现

#!/bin/env bash
#产生1000个以139开头的电话号码并保存文件phonenum.txt
file=/media/zxl/软件/develop/workspace/phonenum.txt
for ((i=1;i<=1000;i++))
do
	n1=$[$RANDOM%10]
	n2=$[$RANDOM%10]
	n3=$[$RANDOM%10]
	n4=$[$RANDOM%10]
	n5=$[$RANDOM%10]
	n6=$[$RANDOM%10]
	n7=$[$RANDOM%10]
	n8=$[$RANDOM%10]
	echo "139$n1$n2$n3$n4$n5$n6$n7$n8" >> $file
done


#!/bin/bash
# random phonenum
# 循环1000次产生电话号码并保存到文件
for i in {1..1000}
do
	n1=$[RANDOM%10]
	n2=$[RANDOM%10]
	n3=$[RANDOM%10]
	n4=$[RANDOM%10]
	n5=$[RANDOM%10]
	n6=$[RANDOM%10]
	n7=$[RANDOM%10]
	n8=$[RANDOM%10]
	echo "139$n1$n2$n3$n4$n5$n6$n7$n8" >> phonenum.txt
done

#!/bin/bash
i=1
while [ $i -le 1000 ]
do
	n1=$[$RANDOM%10]
	n2=$[$RANDOM%10]
	n3=$[$RANDOM%10]
	n4=$[$RANDOM%10]
	n5=$[$RANDOM%10]
	n6=$[$RANDOM%10]
	n7=$[$RANDOM%10]
	n8=$[$RANDOM%10]
	echo "139$n1$n2$n3$n4$n5$n6$n7$n8" >> phonenum.txt
	let i++
done

continue:继续，跳过本次循环，执行下一次循环
break:打断，执行循环体外的代码do..done外
exit:退出程序


#!/bin/bash
for i in {1..1000}
do
	n1=$[$RANDOM%10]
	n2=$[$RANDOM%10]
	n3=$[$RANDOM%10]
	n4=$[$RANDOM%10]
	n5=$[$RANDOM%10]
	n6=$[$RANDOM%10]
	n7=$[$RANDOM%10]
	n8=$[$RANDOM%10]
	echo "139$n1$n2$n3$n4$n5$n6$n7$n8" >> phonenum.txt
done

#!/bin/bash
#create phone num file
for ((i=1;i<=1000;i++))
do
	n1=$[$RANDOM%10]
	n2=$[$RANDOM%10]
	n3=$[$RANDOM%10]
	n4=$[$RANDOM%10]
	n5=$[$RANDOM%10]
	n6=$[$RANDOM%10]
	n7=$[$RANDOM%10]
	n8=$[$RANDOM%10]
	echo "139$n1$n2$n3$n4$n5$n6$n7$n8" |tee -a phonenum.txt
done

#!/bin/bash
count=0
while true
do
	n1=$[$RANDOM%10]
	n2=$[$RANDOM%10]
	n3=$[$RANDOM%10]
	n4=$[$RANDOM%10]
	n5=$[$RANDOM%10]
	n6=$[$RANDOM%10]
	n7=$[$RANDOM%10]
	n8=$[$RANDOM%10]
	echo "139$n1$n2$n3$n4$n5$n6$n7$n8" |tee -a phonenum.txt && let count++
	if [ $count -eq 1000 ];then
		break
	fi
done