Bugs item #1220113, was opened at 2005-06-14 07:04 Message generated for change (Comment added) made by astrand You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=105470&aid=1220113&group_id=5470
Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: None Group: None >Status: Closed >Resolution: Rejected Priority: 5 Submitted By: Stuart Bishop (zenzen) Assigned to: Peter Åstrand (astrand) Summary: subprocess call() helper should close stdin if PIPE Initial Comment: The following code snippet should die instead of hang. >>> from subprocess import call, PIPE >>> rv = call(['/usr/bin/bzip2', '-c'], stdout=PIPE, stdin=PIPE) It makes no sense not to close stdin if it is PIPE because the stream cannot be accessed. The use case for this is ensuring a subprocess that detects if it is connected to a terminal or not runs in 'batch' mode, and that it will die instead of hang if it unexpectidly attempts to read from stdin. Workaround is to use Popen instead. ---------------------------------------------------------------------- >Comment By: Peter Åstrand (astrand) Date: 2005-06-21 18:08 Message: Logged In: YES user_id=344921 >It makes no sense not to close stdin if it is PIPE >because the stream cannot be accessed True, but what if you actually *want* to create an inaccessible pipe, and give it to the child? Currently, the call() wrapper is *very* short and simple. I think this is very good. For example, it allows us to document it in two sentences. You get what you ask for: If you use call() with strange arguments, you'll get a somewhat strange behavíour. I see no point in introducing lots of sanity checks in the wrapper functions. >The use case for this is ensuring a subprocess that >detects if it is connected to a terminal or not runs in >batch' mode, and that it will die instead of hang if >it unexpectidly attempts to read from stdin I'm not sure I understand what you want, but if you want to have stdin connected to a closed file descriptor, just pass one: >>> from subprocess import call, PIPE >>> rv = call(['/usr/bin/bzip2', '-c'], stdout=PIPE, stdin=4711) (Of course, you should verify that 4711 is unused.) If you don't agree with me, post to python-dev for discussion. ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=105470&aid=1220113&group_id=5470 _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
