的Runtime.exec（）BUG：挂起而不提供一个Process对象

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问题描述

不管我用这样的：

process = Runtime.getRuntime().exec("logcat -d time");

或

process = new ProcessBuilder()
              .command("logcat", "-d", "time")
              .redirectErrorStream(true)
              .start();

我得到相同的结果：它常常挂EXEC（），或在启动（）调用，不管是什么我试图做！运行该线程甚至不能用了Thread.interrupt中断（）！子进程肯定是开始，如果杀了上面的命令返回。

I get the same results: it often hangs within the exec() or start() call, no matter what I tried to do!The thread running this cannot even be interrupted with Thread.interrupt()! The child process is definitely started and if killed the above commands return.

这些要求可能会失败的第一次尝试，所以没有办法读取它们的输出！我也可以用一个简单的苏-c杀XXX命令行，同样的结果！

These calls may fail on first attempt, so THERE IS NO WAY TO READ THEIR OUTPUT! I can also use a simple "su -c kill xxx" command line, same result!

编辑：开始调试java_lang_ProcessManager.cpp文件中的NDK项目，一些调试日志！因此，这里是我发现至今，叉（）后父做到这一点：

Started debugging the java_lang_ProcessManager.cpp file in an NDK project with some debugging logs! So here is what I found so far, after the fork() the parent does this:

int result;
int count = read(statusIn, &result, sizeof(int));            <- hangs there
close(statusIn);

虽然子进程不应该阻止它：这就是孩子做（如果在所有的启动！）：

    // Make statusOut automatically close if execvp() succeeds.
    fcntl(statusOut, F_SETFD, FD_CLOEXEC);                      <- make the parent will not block

    // Close remaining unwanted open fds.
    closeNonStandardFds(statusOut, androidSystemPropertiesFd);  <- hangs here sometimes

    ...

    execvp(commands[0], commands);

    // If we got here, execvp() failed or the working dir was invalid.
    execFailed:
        int error = errno;
        write(statusOut, &error, sizeof(int));
        close(statusOut);
        exit(error);

孩子可能会失败，2重现的原因：1子code未运行，但父母认为这是！2-子块上 closeNonStandardFds（statusOut，androidSystemPropertiesFd）;

The child can fail for 2 reproducible reasons: 1- child code is not running, but the parent believes it is!2- child blocks on closeNonStandardFds(statusOut, androidSystemPropertiesFd);

在这两种情况下的僵局父读（statusIn ...）结束！和一子过程是左死（和不能被访问，PID未知，没有过程对象）！

In either case the read(statusIn...) in the parent ends in deadlock! and a child process is left dead (and cannot be accessed, pid unknown, no Process object)!

the

的Runtime.exec（）BUG：挂起而不提供一个Process对象

问题描述

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