systemd sd_bus_message_new_method_error 3 sd_bus_message_new_method_error sd_bus_message_new_method_errorf sd_bus_message_new_method_errno sd_bus_message_new_method_errnof Create a an error reply for a method call #include <systemd/sd-bus.h> int sd_bus_message_new_method_error sd_bus_message *call sd_bus_message **m const sd_bus_error *e int sd_bus_message_new_method_errorf sd_bus_message *call sd_bus_message **m const char *name const char *format … int sd_bus_message_new_method_errno sd_bus_message *call sd_bus_message **m int error const sd_bus_error *p int sd_bus_message_new_method_errnof sd_bus_message *call sd_bus_message **m int error const char *format … The sd_bus_message_new_method_error() function creates a new bus message object that is an error reply to the call message, and returns it in the m output parameter. The error information from error e is appended: the name field of e is used as the error identifier in the reply header (for example an error name such as org.freedesktop.DBus.Error.NotSupported or the equivalent symbolic SD_BUS_ERROR_NOT_SUPPORTED), and the message field is set as the human readable error message string if present. The error e must have the name field set, see sd_bus_error_is_set3. The sd_bus_message_new_method_errorf() function creates an error reply similarly to sd_bus_message_new_method_error(), but instead of a ready error structure, it takes an error identifier string name, plus a printf3 format string format and corresponding arguments. An error reply is sent with the error identifier name and the formatted string as the message. name and format must not be NULL. The sd_bus_message_new_method_errno() function creates an error reply similarly to sd_bus_message_new_method_error(), but in addition to the error structure p, it takes an errno3 error value in parameter error. If the error p is set (see sd_bus_error_is_set3), it is used in the reply. Otherwise, error is translated to an error identifier and used to create a new error structure using sd_bus_error_set_errno3 and that is used in the reply. (If error is zero, no error is actually set, and an error reply with no information is created.) The sd_bus_message_new_method_errnof() function creates an error reply similarly to sd_bus_message_new_method_error(). It takes an errno3 error value in parameter error, plus a printf3 format string format and corresponding arguments. %m may be used in the format string to refer to the error string corresponding to the specified errno code. The error message is initialized using the error identifier generated from error and the formatted string. (If error is zero, no error is actually set, and an error reply with no information is created.) These functions return 0 if the error reply was successfully created, and a negative errno-style error code otherwise. Returned errors may indicate the following problems: -EINVAL The call message call or the output parameter m are NULL. Message call is not a method call message. The error error parameter to sd_bus_message_new_method_error is not set, see sd_bus_error_is_set3. -EPERM Message call has been sealed. -ENOTCONN The bus to which message call is attached is not connected. -ENOMEM Memory allocation failed. systemd1, sd-bus3