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NAME |SYNOPSIS |DESCRIPTION |RETURN VALUE |NOTES |SEE ALSO |COLOPHON | |
SD_BUS...D_ERROR(3) sd_bus_message_new_method_errorSD_BUS...D_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 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, interror,const sd_bus_error *p);int sd_bus_message_new_method_errnof(sd_bus_message *call,sd_bus_message **m,interror,const char *format, ...);
Thesd_bus_message_new_method_error()function creates a new bus message object that is an error reply to thecall message, and returns it in them output parameter. The error information from errore is appended: thename field ofe 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 symbolicSD_BUS_ERROR_NOT_SUPPORTED), and themessage field is set as the human-readable error message string if present. The errore must have thename field set, seesd_bus_error_is_set(3). Thesd_bus_message_new_method_errorf()function creates an error reply similarly tosd_bus_message_new_method_error(), but instead of a ready error structure, it takes an error identifier stringname, plus aprintf(3) format stringformat and corresponding arguments. An error reply is sent with the error identifiername and the formatted string as the message.name andformat must not beNULL. Thesd_bus_message_new_method_errno()function creates an error reply similarly tosd_bus_message_new_method_error(), but in addition to the error structurep, it takes anerrno(3) error value in parametererror. If the errorp is set (seesd_bus_error_is_set(3)), it is used in the reply. Otherwise,error is translated to an error identifier and used to create a new error structure usingsd_bus_error_set_errno(3) and that is used in the reply. (Iferror is zero, no error is actually set, and an error reply with no information is created.) Thesd_bus_message_new_method_errnof()function creates an error reply similarly tosd_bus_message_new_method_error(). It takes anerrno(3) error value in parametererror, plus aprintf(3) format stringformat 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 fromerrorand the formatted string. (Iferror 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.Errors Returned errors may indicate the following problems:-EINVAL The call messagecall or the output parameterm areNULL. Messagecall is not a method call message. The errore parameter tosd_bus_message_new_method_error()is not set, seesd_bus_error_is_set(3).-EPERM Messagecall has been sealed.-ENOTCONN The bus to which messagecall is attached is not connected.-ENOMEM Memory allocation failed.
Functions described here are available as a shared library, which can be compiled against and linked to with thelibsystemd pkg-config(1) file. The code described here usesgetenv(3), which is declared to be not multi-thread-safe. This means that the code calling the functions described here must not callsetenv(3) from a parallel thread. It is recommended to only do calls tosetenv()from an early phase of the program when no other threads have been started.
systemd(1),sd-bus(3)
This page is part of thesystemd (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 2025-08-11. (At that time, the date of the most recent commit that was found in the repository was 2025-08-11.) 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 isnot part of the original manual page), send a mail to man-pages@man7.orgsystemd 258~rc2SD_BUS...D_ERROR(3)Pages that refer to this page:sd-bus(3), sd_bus_message_get_type(3), sd_bus_message_new(3), sd_bus_reply_method_error(3), systemd.directives(7), systemd.index(7)
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