guy@sun.uucp (Guy Harris) (11/11/85)
(Redirected to net.unix because it has nothing to do with C.) > I'm afraid that jss shows his UCB orientation in the above. Well, actually the "Berkeley.EDU" in his name was there because his message was to the ARPANET INFO-C mailing list, and got gatewayed onto "net.lang.c" by the gateway machine for that mailing list/newsgroup, which is (surprise!) UCB-VAX.Berkeley.EDU. > UNIX does have file and record locking (byterange) in the kernel. Make that "some UNIX implementations have file and record locking (byte range) in the kernel." Some which don't include V7 2.9BSD 32/V 4.xBSD System III System V, Release 1 System V, Release 2, Version N, for values of N less than some machine-dependent value - yes, it seems to be a different value for VAX S5R2 and 3B20 S5R2 > (I know that there are no named semaphores in UNIX. It sounds like an > interesting idea.) What's in a name? S5's semaphores can be referred to by a 32-bit unique identifier, which could be considered a name. There is a routine "ftok" which turns a file name into a 32-bit unique identifier by jamming the device and i-number of that file together with an 8-bit code; this can be used as a way of binding a name in the file system to a semaphore set. Guy Harris