--- a/mercurial/utils/procutil.py	Mon Jan 06 14:15:40 2025 -0500
+++ b/mercurial/utils/procutil.py	Sun Jan 05 21:03:17 2025 -0500
@@ -55,10 +55,10 @@
     """Dummy file object to simulate closed stdio behavior"""
 
     def readinto(self, b):
-        raise IOError(errno.EBADF, 'Bad file descriptor')
+        raise OSError(errno.EBADF, 'Bad file descriptor')
 
     def write(self, b):
-        raise IOError(errno.EBADF, 'Bad file descriptor')
+        raise OSError(errno.EBADF, 'Bad file descriptor')
 
 
 class LineBufferedWrapper: