You can use @func{file_deny_write} to prevent writes to an open file.
Calling @func{file_allow_write} on the file will re-enable them (unless
the file is denied writes by another opener). Closing a file will also
-re-enable writes.
+re-enable writes. Thus, to deny writes to process's executable, you
+must keep it open as long as the process is still running.
@node Project 2 FAQ
@section FAQ