NAME

       sd_bus_set_description, sd_bus_get_description, sd_bus_set_anonymous, sd_bus_is_anonymous,
       sd_bus_set_trusted, sd_bus_is_trusted, sd_bus_set_allow_interactive_authorization,
       sd_bus_get_allow_interactive_authorization, sd_bus_get_scope, sd_bus_get_tid,
       sd_bus_get_unique_name - Set or query properties of a bus object

SYNOPSIS

       #include <systemd/sd-bus.h>

       int sd_bus_set_description(sd_bus *bus, const char *description);

       int sd_bus_get_description(sd_bus *bus, const char **description);

       int sd_bus_set_anonymous(sd_bus *bus, int b);

       int sd_bus_is_anonymous(sd_bus *bus);

       int sd_bus_set_trusted(sd_bus *bus, int b);

       int sd_bus_is_trusted(sd_bus *bus);

       int sd_bus_set_allow_interactive_authorization(sd_bus *bus, int b);

       int sd_bus_get_allow_interactive_authorization(sd_bus *bus);

       int sd_bus_get_scope(sd_bus *bus, const char **scope);

       int sd_bus_get_tid(sd_bus *bus, pid_t *tid);

       int sd_bus_get_unique_name(sd_bus *bus, const char **unique);

DESCRIPTION

       sd_bus_set_description() sets the description string that is used in logging to the
       specified string. The string is copied internally and freed when the bus object is
       deallocated. The description argument may be NULL, in which case the description is unset.
       This function must be called before the bus is started.

       sd_bus_get_description() returns a description string in description. This string may have
       been previously set with sd_bus_set_description() or sd_bus_open_with_description(3) or
       similar. If not set this way, a default string like "system" or "user" will be returned
       for the system or user buses, and -ENXIO otherwise.

       sd_bus_set_anonymous() enables or disables "anonymous authentication", i.e. lack of
       authentication, of the bus peer. This function must be called before the bus is started.
       See the D-Bus Authentication Mechanisms[1] section of the D-Bus specification for details.

       sd_bus_is_anonymous() returns true if the bus connection allows anonymous authentication
       (in the sense described in previous paragraph).

       sd_bus_set_trusted() sets the "trusted" state on the bus object. If true, all connections
       on the bus are trusted and access to all privileged and unprivileged methods is granted.
       This function must be called before the bus is started.

       sd_bus_is_trusted() returns true if the bus connection is trusted (in the sense described
       in previous paragraph).

       sd_bus_set_allow_interactive_authorization() enables or disables interactive authorization
       for method calls. If true, messages are marked with the ALLOW_INTERACTIVE_AUTHORIZATION
       flag specified by the D-Bus[2] specification, informing the receiving side that the caller
       is prepared to wait for interactive authorization, which might take a considerable time to
       complete. If this flag is set, the user may be queried for passwords or confirmation via
       polkit[3] or a similar framework.

       sd_bus_get_allow_interactive_authorization() returns true if interactive authorization is
       allowed and false if not.

       sd_bus_get_scope() stores the scope of the given bus object in scope. The scope of the
       system bus is "system". The scope of a user session bus is "user". If the given bus object
       is not the system or a user session bus, sd_bus_get_scope() returns an error.

       sd_bus_get_tid() stores the kernel thread id of the thread associated with the given bus
       object in tid. If bus is a default bus object obtained by calling one of the functions of
       the sd_bus_default(3) family of functions, it stores the thread id of the thread the bus
       object was created in. Otherwise, if the bus object is attached to an event loop, it
       stores the thread id of the thread the event loop object was created in. If bus is not a
       default bus object and is not attached to an event loop, sd_bus_get_tid() returns an
       error.

       sd_bus_get_unique_name() stores the unique name of the bus object on the bus in unique.
       See The D-Bus specification[4] for more information on bus names. Note that the caller
       does not own the string stored in unique and should not free it.

RETURN VALUE

       On success, these functions return a non-negative integer. On failure, they return a
       negative errno-style error code.

   Errors
       Returned errors may indicate the following problems:

       -EINVAL
           An argument is invalid.

       -ENOPKG
           The bus cannot be resolved.

       -EPERM
           The bus has already been started.

       -ECHILD
           The bus was created in a different process, library or module instance.

       -ENOMEM
           Memory allocation failed.

       -ENODATA
           The bus object passed to sd_bus_get_scope() was not a system or user session bus.

           Added in version 246.

       -ENXIO
           The bus object passed to sd_bus_get_tid() was not a default bus object and is not
           attached to an event loop.

           The bus object passed to sd_bus_get_description() did not have a description.

           Added in version 246.

NOTES

       Functions described here are available as a shared library, which can be compiled against
       and linked to with the libsystemd pkg-config(1) file.

       The code described here uses getenv(3), which is declared to be not multi-thread-safe.
       This means that the code calling the functions described here must not call setenv(3) from
       a parallel thread. It is recommended to only do calls to setenv() from an early phase of
       the program when no other threads have been started.

HISTORY

       sd_bus_set_description(), sd_bus_get_description(), sd_bus_set_anonymous(),
       sd_bus_set_trusted(), sd_bus_set_allow_interactive_authorization(), and
       sd_bus_get_allow_interactive_authorization() were added in version 240.

       sd_bus_is_anonymous(), sd_bus_is_trusted(), sd_bus_get_scope(), sd_bus_get_tid(), and
       sd_bus_get_unique_name() were added in version 246.

SEE ALSO

       systemd(1), sd-bus(3), sd_bus_default_user(3), sd_bus_default_system(3),
       sd_bus_open_user(3), sd_bus_open_system(3)

NOTES

        1. D-Bus Authentication Mechanisms
           view-source:https://dbus.freedesktop.org/doc/dbus-specification.html#auth-mechanisms

        2. D-Bus
           view-source:https://dbus.freedesktop.org/doc/dbus-specification.html

        3. polkit
           https://www.freedesktop.org/wiki/Software/polkit

        4. The D-Bus specification
           https://dbus.freedesktop.org/doc/dbus-specification.html#message-protocol-names-bus