New submission from Sebastian Bank <sebastian.b...@uni-leipzig.de>:
AFAIU, the change for https://bugs.python.org/issue19764 broke the following usage of subprocess on Windows (re-using a subprocess.STARTUPINFO instance to hide the command window): import os, subprocess STARTUPINFO = subprocess.STARTUPINFO() STARTUPINFO.dwFlags |= subprocess.STARTF_USESHOWWINDOW STARTUPINFO.wShowWindow = subprocess.SW_HIDE # raises OSError: [WinError 87] # in the second loop iteration starting with Python 3.7 for i in range(2): print(i) with open(os.devnull, 'w') as stderr: subprocess.check_call(['attrib'], stderr=stderr, startupinfo=STARTUPINFO) AFAICT, this works on Python 2.7, 3.4, 3.5, and 3.6 I think the documentation in https://docs.python.org/3/library/subprocess.html#windows-popen-helpers does not mention that every Popen call should be done with a fresh instance, so either the documentation needs to be changed, or the implementation (e.g. by deep-copying the instance). See also https://bugs.python.org/issue19764#msg320784 ---------- components: Library (Lib) messages: 321047 nosy: eryksun, vstinner, xflr6 priority: normal severity: normal status: open title: subprocess: reusing STARTUPINFO breaks under 3.7 (Windows) type: behavior versions: Python 3.7 _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue34044> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
