NAME

       sd_bus_set_fd - Set the file descriptors to use for bus communication

SYNOPSIS

       #include <systemd/sd-bus.h>

       int sd_bus_set_fd(sd_bus *bus, int input_fd, int output_fd);

DESCRIPTION

       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 via
       sd_bus_start(3).

       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.

RETURN VALUE

       On success, sd_bus_set_fd() returns a non-negative integer. On failure, it returns a negative errno-style
       error code.

   Errors
       Returned errors may indicate the following problems:

       -EINVAL
           An invalid bus object was passed.

           Added in version 248.

       -ECHILD
           The bus connection was allocated in a parent process and is being reused in a child process after
           fork().

           Added in version 248.

       -EBADF
           An invalid file descriptor was passed to sd_bus_set_fd().

           Added in version 248.

       -ENOPKG
           The bus cannot be resolved.

           Added in version 248.

       -EPERM
           The bus connection has already been started.

           Added in version 248.

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_fd() was added in version 248.

SEE ALSO

       systemd(1), sd-bus(3), sd_bus_get_fd(3), sd_bus_start(3)

systemd 255                                                                                     SD_BUS_SET_FD(3)