subprocess.check_output仍然打印在標準輸出

我想從一個變量從commande 得到stdout輸出經過一些研究後，我發現subprocess.check_output（cmd）做得很好！但它仍然在stdout中輸出一些輸出！subprocess.check_output仍然打印在標準輸出

cmd = ["openssl","rsa", "-in","pubkey.pem","-pubin","-text","-modulus"] 
output = subprocess.check_output(cmd)

我得到了我想要在我的輸出變量，但它仍然打印我

writing RSA key

，並在輸出無功，我有

'Public-Key: (576 bit)\nModulus:\n 00:c2:cb:b2:4f:db:f9:23:b6:12:68:e3:f1:1a:38:\n 96:de:45:74:b3:ba:58:73:0c:bd:65:29:38:86:4e:\n 22:23:ee:eb:70:4a:17:cf:d0:8d:16:b4:68:91:a6:\n 14:74:75:99:39:c6:e4:9a:af:e7:f2:59:55:48:c7:\n 4c:1d:7f:b8:d2:4c:d1:5c:b2:3b:4c:d0:a3\nExponent: 65537 (0x10001)\nModulus=C2CBB24FDBF923B61268E3F11A3896DE4574B3BA58730CBD652938864E2223EEEB704A17CFD08D16B46891A61474759939C6E49AAFE7F2595548C74C1D7FB8D24CD15CB23B4CD0A3\n-----BEGIN PUBLIC KEY-----\nMGQwDQYJKoZIhvcNAQEBBQADUwAwUAJJAMLLsk/b+SO2Emjj8Ro4lt5FdLO6WHMM\nvWUpOIZOIiPu63BKF8/QjRa0aJGmFHR1mTnG5Jqv5/JZVUjHTB1/uNJM0VyyO0zQ\nowIDAQAB\n-----END PUBLIC KEY-----\n'

pubkey.pem的內容是：

-----BEGIN PUBLIC KEY----- 
MGQwDQYJKoZIhvcNAQEBBQADUwAwUAJJAMLLsk/b+SO2Emjj8Ro4lt5FdLO6WHMM 
vWUpOIZOIiPu63BKF8/QjRa0aJGmFHR1mTnG5Jqv5/JZVUjHTB1/uNJM0VyyO0zQ 
owIDAQAB 
-----END PUBLIC KEY-----

Thanx for help：D

來源

2017-06-20 Nazime Lakehal

check_output允許您將stderr重定向到文件描述符。我已將stderr重定向到下面的「/ dev/null」，我想它會給你想要的東西：

dev_null = open(os.devnull, 'w') 
output = subprocess.check_output(cmd, stderr=dev_null)

來源

2017-06-20 02:56:28 pynewbie

哦，非常感謝！如果我想在變量中獲得stderr輸出？：d –

subprocess.check_output仍然打印在標準輸出

回答

相關問題