----- Ursprüngliche Mail ----- > Von: "Marko Petrović" <petrovicmarko2...@gmail.com> > About using -1 for uid and gid, in documentation for chown it is stated > that -1 shall be used if the desired value should not be changed, since > normally chown(2) accepts both uid and gid for changing in one system > call. > In the concrete implementation, since the underlying type is unsigned > int, the -1 will be written in 2's complement and then treated as an > unsigned positive number. For the size of 4 bytes for unsigned int, the > resulting number is 4294967295. That is also the maximum possible number > of users on Linux, but Linux user IDs go from 0 to 4294967294 so that > last one is outside UID space and reserved as "don't change" flag for > chown(2).
You're totally right. I should have checked the manpage before. > In regard to the store of values in platform independent way, in my > humble opinion, Johannes' recommendation may be preferred (storing all > permissions in one string) because besides this it also solves the > problem of one setxattr() succeding and other failing (for whatever > reason may that happen) in uml_chown(). Storing them as string is also fine by me. :-) Thanks, //richard _______________________________________________ linux-um mailing list linux-um@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-um
