sys.stdin.read() 将继续阅读直到 EOF 所以在你的 paramiko 脚本中你需要关闭 stdin(从 exec_command() 返回).但是如何?

sys.stdin.read() will keep reading until EOF so in your paramiko script you need to close the stdin (returned from exec_command()). But how?

根据 Paramiko 的文档 (v1.16):

According to Paramiko's doc (v1.16):

警告:要正确模拟从套接字的 makefile() 方法创建的文件对象，需要一个 Channel 及其 ChannelFile 应该能够独立关闭或垃圾收集.目前，关闭 ChannelFile 只会刷新缓冲区.

Warning: To correctly emulate the file object created from a socket’s makefile() method, a Channel and its ChannelFile should be able to be closed or garbage-collected independently. Currently, closing the ChannelFile does nothing but flush the buffer.

2.stdin.channel.close() 也有问题.

由于 stdin、stdout 和 stderr 都共享一个通道，stdin.channel.close()也将关闭 stdout 和 stderr 这不是预期的.

2. stdin.channel.close() also has problem.

Since stdin, stdout and stderr all share one single channel, stdin.channel.close() will also close stdout and stderr which is not expected.

正确的解决方案是使用 stdin.channel.shutdown_write() 不允许写入通道但仍然允许从通道读取所以 stdout.read() 和stderr.read() 仍然可以工作.

The correct solution is to use stdin.channel.shutdown_write() which disallows writing to the channel but still allows reading from the channel so stdout.read() and stderr.read() would still work.

看下面的例子，看看stdin.channel.close()和stdin.channel.shutdown_write()的区别.

See following example to see the difference between stdin.channel.close() and stdin.channel.shutdown_write().

[STEP 101] # cat foo.py
import paramiko, sys, time

ssh = paramiko.SSHClient()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy() )
ssh.connect(hostname='127.0.0.1', username='root', password='password')
cmd = "sh -c 'read v; sleep 1; echo $v'"
stdin, stdout, stderr = ssh.exec_command(cmd)
if sys.argv[1] == 'close':
    stdin.write('hello world\n')
    stdin.flush()
    stdin.channel.close()
elif sys.argv[1] == 'shutdown_write':
    stdin.channel.send('hello world\n')
    stdin.channel.shutdown_write()
else:
    raise Exception()
sys.stdout.write(stdout.read() )
[STEP 102] # python foo.py close           # It outputs nothing.
[STEP 103] # python foo.py shutdown_write  # This works fine.
hello world
[STEP 104] #