sd_bus_set_fd - Set the file descriptors to use for bus communication
int sd_bus_set_fd(sd_bus *bus,
sd_bus_set_fd() sets the file descriptors used to communicate by a bus
connection object. Both input_fd and output_fd must be valid
file descriptors, referring to stream-based file objects (e.g. a stream
socket, a pair of pipes or FIFOs, or even a TTY device). input_fd must
be readable, and output_fd must be writable. The same file descriptor
may be used (and typically is used) as both the input and the output file
descriptor. This function must be called before the bus connection is started
The bus connection object will take possession of the passed file
descriptors and will close them automatically when it is freed. Use
sd_bus_set_close_on_exit(3) to turn off this behaviour.
On success, sd_bus_set_fd() returns a non-negative integer. On failure,
it returns a negative errno-style error code.
Returned errors may indicate the following problems:
An invalid bus object was passed.
The bus connection was allocated in a parent process and
is being reused in a child process after fork().
An invalid file descriptor was passed to
The bus cannot be resolved.
The bus connection has already been started.
These APIs are implemented as a shared library, which can be compiled and linked
to with the libsystemd pkg-config(1) file.