我经常遇到$? $0 $1 $2 etc....shell脚本,我知道的是$?返回最后一个命令的退出状态
echo "this will return 0"
echo $?
但其他人做了什么？他们叫什么,还有更多吗？也许就像$ 3 $ 4 $ 5 ...
filter="yes"
phonenumbers=(123 456 789 987 654 321)
echo "checking inbox now..."
myphonenumber=(7892)
if [[ "$filter" == "yes" ]]; then
case "${phonenumbers[@]}" in
*"$myphonenumber"*) echo "filter is on, phone number matches"
;;
!="$myphonenumber") echo "filter is on but the phone number doesn't match"
;;
esac
fi
if [[ "$filter" == "no" ]]; then
echo "filter off"
fi
我尝试运行该脚本但它不起作用，我应该如何显示该filter is on but the phone number doesn't match部分？我还在学习，我知道我可以用if else语句来做到这一点，但我想知道我是否也可以做到case。
用于重置 USB 蜂窝调制解调器的 AT 命令序列是什么？
是否有可以使用的单个 AT 命令？或者它是否需要多个序列才能重置 USB 蜂窝调制解调器？
我有华为 E272 和 E220，但是如果有任何标准 AT 命令，我也对通用命令序列感兴趣。
出于某种原因,我无法使用bash构建我的脚本,唯一的方法是使用ash,我有这个短信自动响应脚本,每个回复必须最多160个字符长,它看起来像这样:
#!/bin/sh
reply="this is a reply message that contains so many words so I have to split it to some parts"
array="${reply:0:5} ${reply:5:5} ${reply:10:5} ${reply:15:5} ${reply:20:5}"
for i in $array
do
echo "send sms with the message: $i"
done
但它最终会像这样:
send sms with the message: this
send sms with the message: is
send sms with the message: a
send sms with the message: reply
send sms with the message: mess
send sms with the message: age …<?php
$filename = '/path/to/foo.txt';
if (file_exists($filename)) {
echo "The file $filename exists";
}
?>
该脚本仅检查文件是否存在,但我该如何做这样的事情？
<?php
$filename = '/path/to/foo.txt';
if (file doesnt exist) {
exit("Your file doesn't exist");
}
?>