the output goes to FILENAME, but the buffer is marked as visiting VISIT.
VISIT is also the file name to lock and unlock for clash detection.
If VISIT is neither t nor nil nor a string,
- that means do not print the \"Wrote file\" message.
+ that means do not display the \"Wrote file\" message.
The optional sixth arg LOCKNAME, if non-nil, specifies the name to
use for locking and unlocking, overriding FILENAME and VISIT.
The optional seventh arg MUSTBENEW, if non-nil, insists on a check