icasefile is LD_PRELOADable wrapper for several libc functions such as open(), stat() and chown(). It allows user to access files regardless of filename case, just like it would be possible with case-insensitive filesystem. This can be helpful with games ported from DOS/Windows to GNU/Linux with datafiles extracted from original source.
Each (supported) system function will first check if the requested file can be found as-is. If the filename contains one or more directories, file (and subdirectories) are searched from each directory. In short, this allows music.dat to match MUSIC.DAT and ../Data/INTERFACE/ui.DLG to match ../data/interface/ui.dlg.
Usage: LD_PRELOAD=/path/to/icasefile.so APPLICATION
If you don't know how to compile or use it, either you don't need or want this.