ARGVMI~1.PIF on Nostr: So yeah, apparently the #Windows #Win32 function `CloseClipboard` doesn't actually ...
So yeah, apparently the #Windows #Win32 function `CloseClipboard` doesn't actually close the clipboard right away.
There is no guarantee that immediately calling `OpenClipboard` will succeed. Even on the same thread.
Which means mutex locking around `OpenClipboard`/`CloseClipboard` won't work. If there is contention, it'll still fail.
The docs say nothing about this.
https://learn.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-closeclipboardFML.
A strategy of “mutex lock, then sleep-and-retry a few times” seems to suffice…
#programming
Published at
2026-06-04 20:25:16 UTCEvent JSON
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"content": "So yeah, apparently the #Windows #Win32 function `CloseClipboard` doesn't actually close the clipboard right away.\n\nThere is no guarantee that immediately calling `OpenClipboard` will succeed. Even on the same thread.\n\nWhich means mutex locking around `OpenClipboard`/`CloseClipboard` won't work. If there is contention, it'll still fail.\n\nThe docs say nothing about this. https://learn.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-closeclipboard\n\nFML.\n\nA strategy of “mutex lock, then sleep-and-retry a few times” seems to suffice…\n\n#programming",
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