[comp.sys.mips] file locking

jtw@lcs.mit.edu (John Wroclawski) (12/11/90)

(RISC/OS 4.51)

The flock() man page says

     flock is emulated using the fcntl(2) mechanism and so file
     locks obtained through the fcntl(2) and lockf(3) mechanisms
     interact with those acquired via flock.

and the fcntl() man page says

     File locks obtained through the fcntl mechanism interact
     with those acquired via flock(2) and lockf(3).


but the lockf() man page says

     File locks obtained through the lockf mechanism do not
     interact in any way with those acquired via flock(2).  They
     do, however, work correctly with the locks claimed by
     fcntl(2).

Unfortunately, I suspect the lockf() page is right, and the others
describe a good idea that didn't get done. Anyone know what's really
going on here?

		-john
		jtw@lcs.mit.edu

datri@convex.com (Anthony A. Datri) (12/11/90)

>     flock is emulated using the fcntl(2) mechanism and so file
>     locks obtained through the fcntl(2) and lockf(3) mechanisms
>     interact with those acquired via flock.

If this is true, Mips is the first vendor that I've seen do it.  One
problem is that lockf/fcntl uses rpc.lockd, which I've not seen be
solid on any platform.

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