| SD_BUS_MESSAGE_NEW_METHOD_ERROR(3) | sd_bus_message_new_method_error | SD_BUS_MESSAGE_NEW_METHOD_ERROR(3) |
.SH "NAME" 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
.SH "SYNOPSIS"
#include <systemd/sd-bus.h>
.HP 864u int
sd_bus_message_new_method_error(sd_bus_message *call,
sd_bus_message **m,
const sd_bus_error *e);
.HP 888u int
sd_bus_message_new_method_errorf(sd_bus_message *call,
sd_bus_message **m,
const char *name,
const char *format, ...);
.HP 864u int
sd_bus_message_new_method_errno(sd_bus_message *call,
sd_bus_message **m, int error,
const sd_bus_error *p);
.HP 888u int
sd_bus_message_new_method_errnof(sd_bus_message *call,
sd_bus_message **m, int error,
const char *format, ...);
.SH "DESCRIPTION"
.PP 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_set(3).
.PP 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 printf(3) 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.
.PP 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 errno(3) error value in
parameter error. If the error p is set (see
sd_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 using sd_bus_error_set_errno(3) 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.)
.PP The sd_bus_message_new_method_errnof() function creates an error
reply similarly to sd_bus_message_new_method_error(). It takes an
errno(3) error value in parameter error, plus a
printf(3) 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.)
.SH "RETURN VALUE"
.PP These functions return 0 if the error reply was successfully created, and
a negative errno-style error code otherwise.
.SS "Errors"
.PP Returned errors may indicate the following problems:
.PP -EINVAL
The call message call or the output parameter m are
NULL.
Message call is not a method call message.
The error e parameter to sd_bus_message_new_method_error() is
not set, see sd_bus_error_is_set(3).
.RE
.PP -EPERM
Message call has been sealed.
.RE
.PP -ENOTCONN
The bus to which message call is attached is not connected.
.RE
.PP -ENOMEM
Memory allocation failed.
.RE
.SH "NOTES"
.PP Functions described here are available as a shared library, which can be
compiled against and linked to with the
libsystemd pkg-config(1) file.
.PP All functions listed here are thread-agnostic and only a single thread
may operate on a given object at any given time. Different threads may
access the same object at different times. Multiple independent objects may
be used from different threads in parallel.
.PP 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.
.SH "SEE ALSO"
.PP systemd(1), sd-bus(3)
| systemd 262.2 |