MAC_GET(3) BSD Library Functions Manual MAC_GET(3)NAME
mac_get_file, mac_get_link, mac_get_fd, mac_get_peer, mac_get_pid,
mac_get_proc — get the label of a file, socket, socket peer or process
Standard C Library (libc, -lc)
mac_get_file(const char *path, mac_t label);
mac_get_link(const char *path, mac_t label);
mac_get_fd(int fd, mac_t label);
mac_get_peer(int fd, mac_t label);
mac_get_pid(pid_t pid, mac_t label);
The mac_get_file() system call returns the label associated with a file
specified by pathname. The mac_get_link() function is the same as
mac_get_file(), except that it does not follow symlinks.
The mac_get_fd() system call returns the label associated with an object
referenced by the specified file descriptor. Note that in the case of a
file system socket, the label returned will be the socket label, which
may be different from the label of the on-disk node acting as a ren‐
dezvous for the socket. The mac_get_peer() system call returns the label
associated with the remote endpoint of a socket; the exact semantics of
this call will depend on the protocol domain, communications type, and
endpoint; typically this label will be cached when a connection-oriented
protocol instance is first set up, and is undefined for datagram proto‐
The mac_get_pid() and mac_get_proc() system calls return the process
label associated with an arbitrary process ID, or the current process.
Label storage for use with these calls must first be allocated and pre‐
pared using the mac_prepare(3) functions. When an application is done
using a label, the memory may be returned using mac_free(3).
[EACCES] A component of path is not searchable, or MAC read
access to the file is denied.
[EINVAL] The requested label operation is not valid for the
object referenced by fd.
[ENAMETOOLONG] The pathname pointed to by path exceeds PATH_MAX, or a
component of the pathname exceeds NAME_MAX.
[ENOENT] A component of path does not exist.
[ENOMEM] Insufficient memory is available to allocate a new MAC
[ENOTDIR] A component of path is not a directory.
SEE ALSOmac(3), mac_free(3), mac_prepare(3), mac_set(3), mac_text(3), posix1e(3),
POSIX.1e is described in IEEE POSIX.1e draft 17. Discussion of the draft
continues on the cross-platform POSIX.1e implementation mailing list. To
join this list, see the FreeBSD POSIX.1e implementation page for more
Support for Mandatory Access Control was introduced in FreeBSD 5.0 as
part of the TrustedBSD Project.
BSD December 21, 2001 BSD