使用Python將命令發送到子殼

Question

我需要在命令啓動後發送命令到shell「MYSHELL>」。

prcs = subprocess.Popen("MYSHELL; cmnd1; cmnd2;",shell=True, 
subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE) 

outputPrcs, err = prcs.communicate() 
print outputPrcs 

只有進入shell的問題被執行，其他命令（cmnd1; cmnd2;）不會被髮送。

結果： MYSHELL>

Answer 1

從docs：

communicate(self, input=None) 
    Interact with process: Send data to stdin. Read data from 
    stdout and stderr, until end-of-file is reached. Wait for 
    process to terminate. The optional input argument should be a 
    string to be sent to the child process, or None, if no data 
    should be sent to the child. 

通知，Wait for process to terminate.我想你需要的是pexpect。它不在標準庫中，但它會做你想做的。

例子：

import pexpect 

process = pexpect.spawn("python") 
process.expect_exact(">>> ") 
process.sendline('print("It works")') 
process.expect("\n.*\n") 
response = process.after.strip() 
print(response) 

輸出：

It works 

Answer 2

如果你想輸入發送到你的shell，那麼你應該把它作爲一個參數在communicate，像這樣：

prcs = subprocess.Popen("MYSHELL",shell=True, 
subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE) 

outputPrcs, err = prcs.communicate("cmnd1; cmnd2;") 
print outputPrcs 

test：

>>> from subprocess import * 
>>> p = Popen("python", shell=True, stdin=PIPE, stdout=PIPE, stderr=PIPE) 
>>> o,e = p.communicate("print 'it works'") 
>>> print o 
it works 

>>>