Hi, Greg, Thomas I find 3 version of MKDEV (actually 2 + makedev)
in include/linux/kdev_t.h #define MINORBITS 20 #define MKDEV(ma,mi) (((ma) << MINORBITS) | (mi)) in inlcude/uapi/linux/kdev_t.h #define MKDEV(ma,mi) ((ma)<<8 | (mi)) in Android bionic #define makedev(__major, __minor) \ ( \ (((__major) & 0xfffff000ULL) << 32) | (((__major) & 0xfffULL) << 8) | \ (((__minor) & 0xffffff00ULL) << 12) | (((__minor) & 0xffULL)) \ ) if I use mknod("renderD128", S_IFCHR|0666, MKDEV(226, 128)); I get wrong device: crw-rw-rw- 1 root graphics 0, 57984 2011-11-11 11:20 renderD128 if I use ("renderD128",S_IFCHR|0666, makedev(226, 128)); I get right device. but, when I use: mknod("card0", S_IFCHR|0666, MKDEV(226, 0)); I can get right device. BR. Ning.