* * calling `fdopen_lock_file()` to get a `FILE` pointer for the
* open file and writing to the file using stdio.
*
+ * Note that the file descriptor returned by hold_lock_file_for_update()
+ * is marked O_CLOEXEC, so the new contents must be written by the
+ * current process, not a spawned one.
+ *
* When finished writing, the caller can:
*
* * Close the file descriptor and rename the lockfile to its final