René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"pty.spawn deadlock","articleBody":"# Bug report\r\n\r\n```\r\n% yes | python3 -c \"import pty; pty.spawn(['cat'])\"\r\ny\r\n...\r\ny^CTraceback (most recent call last):\r\n  File \"\u003cstring\u003e\", line 1, in \u003cmodule\u003e\r\n  File \"/usr/lib/python3.10/pty.py\", line 181, in spawn\r\n    _copy(master_fd, master_read, stdin_read)\r\n  File \"/usr/lib/python3.10/pty.py\", line 161, in _copy\r\n    _writen(master_fd, data)\r\n  File \"/usr/lib/python3.10/pty.py\", line 127, in _writen\r\n    n = os.write(fd, data)\r\nKeyboardInterrupt\r\n```\r\n\r\nYou will see 2048 lines of y due to tty echo, then the output stops and hangs forever.\r\nBoth python and cat block on write, waiting each other consume something from pty buffer.\r\n\r\n# Your environment\r\n\r\nTested on Linux/macOS with CPython 3.10.\n\n\u003c!-- gh-linked-prs --\u003e\n### Linked PRs\n* gh-96639\n* gh-104655\n\u003c!-- /gh-linked-prs --\u003e\n","author":{"url":"https://github.com/zhangyoufu","@type":"Person","name":"zhangyoufu"},"datePublished":"2022-09-03T05:27:15.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":4},"url":"https://github.com/96522/cpython/issues/96522"}