I see from one of the comments on my patch #103459 that there is a history to this issue (patch #103154) I had assumed that renaming modules and possibly breaking existing code was not an option, but this seems to have been considered in the discussion on that earlier patch. Is there any consensus on how to deal with this ? I would *really* like to get SOME fix -- either my patch, or a renaming of FCNTL, TERMIOS, SOCKET, into the next release. It's not clear to me whether the issues on other systems are the same. On mac-osx, the OS is BSD unix based and when using a unix file system, it's case sensitive. But the standard filesystem is Apple's HFS+, which is case preserving but case insensitive. ( That means that opening "abc" will succeed if there is a file named "abc", "ABC", "Abc" , "aBc" ... , but a directory listing will show "abc" ) I had guessed that the CHECK_IMPORT_CASE ifdefs and the corresponding configure switch were there for this sort of problem, and all I had to do was add a macosx implementation of check_case(), but returning false from check_case causes the search to fail -- it does not continue until it find a matching module. So it appears that I don't understand the issues on other platforms and what CHECK_IMPORT_CASE intends to fix. -- Steve Majewski