int sd_bus_message_copy(sd_bus_message *m, sd_bus_message *source, int all);
sd_bus_message_copy() copies the contents from message source to m. If all is false, a single complete type is copied (basic or container). If all is true, the contents are copied until the end of the currently open container or the end of source.
On success, this call returns true if anything was copied, and false if there was nothing to copy. On failure, it returns a negative errno-style error code.
Returned errors may indicate the following problems:
source or m are NULL.
Message m has been sealed or source has not been sealed.
Destination message is in invalid state.
Destination message cannot be appended to.
Memory allocation failed.
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.
systemd(1), sd-bus(3), sd_bus_message_append(3)
sd-bus(3), systemd.directives(7), systemd.index(7).