sd_bus_message_get_signature, sd_bus_message_is_empty, sd_bus_message_has_signature - Query bus message signature
#include <systemd/sd-bus.h> const char* sd_bus_message_get_signature(sd_bus_message *message, int complete); int sd_bus_message_is_empty(sd_bus_message *message); int sd_bus_message_has_signature(sd_bus_message *message, const char *signature);
sd_bus_message_get_signature() returns the signature of message message. If complete is true, the signature of the whole message is returned, and just the signature of the currently open container otherwise. sd_bus_message_is_empty() returns true if the message is empty, i.e. when its signature is empty. sd_bus_message_has_signature() returns true if the signature of the message message matches given signature. Parameter signature may be NULL, this is treated the same as an empty string, which is equivalent to calling sd_bus_message_is_empty().
On success, sd_bus_message_get_signature() returns the signature, and NULL on error. The other functions return 0 or a positive integer on success. On failure, they return a negative errno-style error code. Errors Returned errors may indicate the following problems: -EINVAL The message parameter is NULL. NULL The message parameter is NULL.
These APIs are implemented as a shared library, which can be compiled and linked to with the libsystemd pkg-config(1) file.
systemd(1), sd-bus(3), sd_bus_message_new(3)
This page is part of the systemd (systemd system and service manager) project. Information about the project can be found at ⟨http://www.freedesktop.org/wiki/Software/systemd⟩. If you have a bug report for this manual page, see ⟨http://www.freedesktop.org/wiki/Software/systemd/#bugreports⟩. This page was obtained from the project's upstream Git repository ⟨https://github.com/systemd/systemd.git⟩ on 2021-06-20. (At that time, the date of the most recent commit that was found in the repository was 2021-06-19.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which is not part of the original manual page), send a mail to firstname.lastname@example.org systemd 249 SD_BUS_MESSAGE_GET_SIGNATURE(3)
Pages that refer to this page: sd-bus(3), systemd.directives(7), systemd.index(7)