无法在QProcess中执行echo命令 [英] Cannot execute echo command in QProcess

问题描述

我想在带有Qt的Ubuntu 10.04 LTS下使用netcat实用程序在我的设备中启动SCPI命令。我的代码如下：

I want to launch a SCPI command in my device using netcat utility under Ubuntu 10.04 LTS with Qt. My code looks like:

env = "echo TRIG | nc 192.168.1.100 23 -q1";
process1.execute(env);
process1.waitForFinished(1000);

此命令不返回任何数据，而只是触发数据获取。
如果将终端使用相同的 echo TRIG | nc 192.168.1.100 23 -q1命令，则一切正常。
从Qt，它不起作用。调试输出为 TRIG | nc 10.0.3.250 23 -q1 ...因此没有 echo。我的设备没有收到TRIG命令。

This command does not return any data but simply triggers the data acquisition. If using terminal with same "echo TRIG | nc 192.168.1.100 23 -q1" command, everything works fine. From Qt, it does not work. The debug output is "TRIG | nc 10.0.3.250 23 -q1" ... so without an "echo". My device does not receive the TRIG command.

您能告诉我我做错了什么吗？
非常感谢。

Could you please advise what I'm doing wrong? Many thanks.

推荐答案

您不能以这种方式在QProcess中使用管道命令（|）。

You can't use the pipe command (|) with QProcess that way.

有几种解决方法：-

您可以调用第一个命令并检索其输出

You can call the first command and retrieve its output before processing it either in Qt or with another call to QProcess.

或者，创建一个从QProcess调用的脚本并检索输出。

Or, create a script that you call from QProcess and retrieve the output.

最后，假设您使用的是Linux / OSX，则可以使用/ bin / bash调用QProcess并将命令传递给它。例如：-

Finally, assuming you're using linux / OSX, you can call QProcess with /bin/bash and pass the command to that. For example: -

env = "/bin/bash \"echo TRIG | nc 192.168.1.100 23 -q1\"";
process1.execute(env);

您可能会找到与Windows的/ bin / bash等效的文件，也许是cmd.exe

You can probably find an equivalent to /bin/bash for windows, perhaps cmd.exe

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