Make the -0 option faking the success of any mode changes (chmod* syscalls).

Change-Id: I73c5c99f2dc968682481cd0f6e57d9761edc7bae
Fix misuse of the "size" argument for the syscalls related to sockets.

Technically, the null-terminating byte may or may not be taken into
account when computing the "size" argument of syscalls related to
sockets.  For example, it may be computed with the SUN_LEN() macro,
this way:

    size = offsetof(struct sockaddr_un, sun_path) + strlen(sockaddr.sun_path)

Change-Id: I07749c542e4262263b71dd307dc5288f6dcf7876