括号扩展与变量？ [英] Brace expansion with variable?

问题描述

#!/bin/sh
for i in {1..5}
do
   echo "Welcome"
done

会的工作，显示欢迎5次。

Would work, displays Welcome 5 times..

#!/bin/sh
howmany=`grep -c $1 /root/file`


for i in {1..$howmany}
do
   echo "Welcome"
done

没有工作...的howmany就等于5因为这是grep的-c文件/根/文件的输出将显示。 $ 1参数1运行脚本时，这是特定的。

Doesn't work... howmany would equal 5 as that is what the output of grep -c file /root/file would display. $1 is parameter 1 which is specific when running the script.

任何想法？

推荐答案

创建一个序列来控制你的循环

create a sequence to control your loop

for i in $(seq 1 $howmany); do
echo "Welcome";
done

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