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Arduino使用变量运行shell命令_Shell_Variables_Arduino_Arduino Yun - Fatal编程技术网

Arduino使用变量运行shell命令

Arduino使用变量运行shell命令,shell,variables,arduino,arduino-yun,Shell,Variables,Arduino,Arduino Yun,在我正在进行的项目的这一部分,我需要帮助,我需要运行一个shell命令,并向它传递一个变量string或char p.runShellCommand("madplay /mnt/sda1/"); 上面是我的shell命令,它可以工作,但是我想在最后一个斜杠后面放一个变量 p.runShellCommand("madplay /mnt/sda1/variable"); 上面的代码是我尝试过的,用我的变量替换变量,但似乎不起作用 我也试过这个,似乎很管用 String hey = "madpla

在我正在进行的项目的这一部分,我需要帮助,我需要运行一个shell命令,并向它传递一个变量string或char

p.runShellCommand("madplay /mnt/sda1/");
上面是我的shell命令,它可以工作,但是我想在最后一个斜杠后面放一个变量

p.runShellCommand("madplay /mnt/sda1/variable");
上面的代码是我尝试过的,用我的变量替换变量,但似乎不起作用

我也试过这个,似乎很管用

String hey = "madplay /mnt/sda1/worldOfTomorrow.mp3";
p.runShellCommand(hey);

这只是字符串连接:

String command= "madplay /mnt/sda1/";
String var = "worldOfTomorrow.mp3";
p.runShellCommand(command+var);
现在,使用所需函数写入
var

String command= "madplay /mnt/sda1/";
String var = getNameOfFile();
p.runShellCommand(command+var);
...
public String getNameOfFile(){
//code retrieving your desired variable by Serial/SDcard/Ethernet....
}

String命令=“madplay/mnt/sda1/”;String var=“worldOfTomorrow.mp3”;p、 runShellCommand(command+var)