paramiko环境变量的问题

423497786

>>> client = paramiko.SSHClient()
>>> client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
>>> client.connect(host, port, user, pwd, timeout = 15)
>>> stdin,stdout,stderr = client.exec_command('echo $a')
>>> stdout.read()
'\n'
>>> stdin,stdout,stderr = client.exec_command('source .bash_profile;echo $a')
>>> stdout.read()
'1\n'
>>>


要手工source .bash_profile才会生效环境变量这是为什么？？？？