HelenOS sources

FAT_ATTR_SYSTEM    60 uspace/app/mkfat/fat_dentry.h     (FAT_ATTR_RDONLY | FAT_ATTR_HIDDEN | FAT_ATTR_SYSTEM | FAT_ATTR_VOLLABEL)
FAT_ATTR_SYSTEM    61 uspace/srv/fs/fat/fat_dentry.h     (FAT_ATTR_RDONLY | FAT_ATTR_HIDDEN | FAT_ATTR_SYSTEM | FAT_ATTR_VOLLABEL)
HelenOS homepage, sources at GitHub