debug1 655 kern/kern_sysctl.c extern struct ctldebug debug0, debug1; debug1 661 kern/kern_sysctl.c &debug0, &debug1, &debug2, &debug3, &debug4, debug1 788 kern/vfs_subr.c struct ctldebug debug1 = { "busyprt", &busyprt }; debug1 656 sys/sysctl.h extern struct ctldebug debug0, debug1, debug2, debug3, debug4;