Re: [TUHS] v7 K&R C

Larry McVoy writes: Enums are implemented badly, but it's possible to do even worse. This is from linux /usr/include/sys/mount.h - can anyone explain the point of it to me? enum { MS_RDONLY = 1, /* Mount read-only. */ #define MS_RDONLY MS_RDONLY MS_NOSUID = 2, /* Ignore suid and sgid bits. */ #define MS_NOSUID MS_NOSUID MS_NODEV = 4, /* Disallow access to device special files. */ #define MS_NODEV MS_NODEV MS_NOEXEC = 8, /* Disallow program execution. */ #define MS_NOEXEC MS_NOEXEC MS_SYNCHRONOUS = 16, /* Writes are synced at once. */ #define MS_SYNCHRONOUS MS_SYNCHRONOUS MS_REMOUNT = 32, /* Alter flags of a mounted FS. */ #define MS_REMOUNT MS_REMOUNT MS_MANDLOCK = 64, /* Allow mandatory locks on an FS. */ #define MS_MANDLOCK MS_MANDLOCK MS_DIRSYNC = 128, /* Directory modifications are synchronous. */ #define MS_DIRSYNC MS_DIRSYNC MS_NOATIME = 1024, /* Do not update access times. */ #define MS_NOATIME MS_NOATIME MS_NODIRATIME = 2048, /* Do not update directory access times. */ #define MS_NODIRATIME MS_NODIRATIME MS_BIND = 4096, /* Bind directory at different place. */ #define MS_BIND MS_BIND MS_MOVE = 8192, #define MS_MOVE MS_MOVE MS_REC = 16384, #define MS_REC MS_REC MS_SILENT = 32768, #define MS_SILENT MS_SILENT MS_POSIXACL = 1 << 16, /* VFS does not apply the umask. */ #define MS_POSIXACL MS_POSIXACL MS_UNBINDABLE = 1 << 17, /* Change to unbindable. */ #define MS_UNBINDABLE MS_UNBINDABLE MS_PRIVATE = 1 << 18, /* Change to private. */ #define MS_PRIVATE MS_PRIVATE MS_SLAVE = 1 << 19, /* Change to slave. */ #define MS_SLAVE MS_SLAVE MS_SHARED = 1 << 20, /* Change to shared. */ #define MS_SHARED MS_SHARED MS_RELATIME = 1 << 21, /* Update atime relative to mtime/ctime. */ #define MS_RELATIME MS_RELATIME MS_KERNMOUNT = 1 << 22, /* This is a kern_mount call. */ #define MS_KERNMOUNT MS_KERNMOUNT MS_I_VERSION = 1 << 23, /* Update inode I_version field. */ #define MS_I_VERSION MS_I_VERSION MS_STRICTATIME = 1 << 24, /* Always perform atime updates. */ #define MS_STRICTATIME MS_STRICTATIME MS_LAZYTIME = 1 << 25, /* Update the on-disk [acm]times lazily. */ #define MS_LAZYTIME MS_LAZYTIME MS_ACTIVE = 1 << 30, #define MS_ACTIVE MS_ACTIVE MS_NOUSER = 1 << 31 #define MS_NOUSER MS_NOUSER };