将控制字符发送到 Java 中的外部进程 [英] sending control charactors to external process in Java

问题描述

我使用以下命令连接到 ubuntu 中的/bin/bash":

I am connecting to "/bin/bash" in ubuntu using:

process = Runtime.getRuntime().exec(cmd);

这里的 cmd 是一个字符串，其中包含我从进程中读取和写入的不同命令.
现在我遇到了一种情况，我使用 ssh 登录到远程机器，在读取写入信息到 ext 进程时，要从远程机器注销，我必须发送控制字符，如:

Here cmd is a String with different commands that i read and write from process.
Now i have come across a situation, where i login to remote machiens using ssh and while reading writing information to ext process, for loggin out from remote machine, i have to send control character like:

CTRL + ] 以优雅地注销会话并返回到我的本地机器.假设 cmd 是 String 类型，我如何将这个 CTRL 字符写入进程?

CTRL + ] in order to logout the session gracefully and come back to my local machine. Assuming the cmd is a String type, how can i write this CTRL chracter to the process?

推荐答案

Control-] 在 ASCII 中相当于 035 八进制.在 Java 中，您可以将其表示为\035".

Control-] in ASCII is equivalent to 035 octal. In Java you can represent this as "\035".

Writer writer = new OutputStreamWriter(process.getOutputStream());
writer.write("\035");
writer.flush();

它也等价于十进制值 29，所以如果你可以写一个值为 29 的字节，那么它也能工作.

It is also equivalent to decimal value of 29 so if you can write a byte with a value of 29 then that will work as well.

OutputStream os = process.getOutputStream();
os.write(29);
os.flush();

我认为 Control-] 与远程程序有关.你说的是telnet?但是写exit\n"也会关闭远程bash.

I assume Control-] has to do with the remote program. You are talking about telnet? However writing "exit\n" will also close the remote bash.

Writer writer = new OutputStreamWriter(process.getOutputStream());
writer.write("exit\n");
writer.flush();

显然，您也可以关闭 OutputStream，它会关闭远程进程的 STDIN.

You can also, obviously, close the OutputStream which closes the STDIN of the remote process.

os.close();

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