sd_bus_error_add_map(3) — Linux manual page


SD_BUS_ERROR_ADD_MAP(3)   sd_bus_error_add_map   SD_BUS_ERROR_ADD_MAP(3)

NAME         top

       sd_bus_error_add_map, sd_bus_error_map, SD_BUS_ERROR_MAP,
       SD_BUS_ERROR_END - Additional sd-dbus error mappings

SYNOPSIS         top

       #include <systemd/sd-bus.h>

       typedef struct {
               const char *name;
               int code;
       } sd_bus_error_map;

       SD_BUS_ERROR_MAP(name, code)


       int sd_bus_error_add_map(const sd_bus_error_map *map);

DESCRIPTION         top

       The sd_bus_error_add_map() call may be used to register
       additional mappings for converting D-Bus errors to Linux
       errno-style errors. The mappings defined with this call are
       consulted by calls such as sd_bus_error_set(3) or
       sd_bus_error_get_errno(3). By default, a number of generic,
       standardized mappings are known, as documented in
       sd-bus-errors(3). Use this call to add further,
       application-specific mappings.

       The function takes a pointer to an array of sd_bus_error_map
       structures. A reference to the specified array is added to the
       lookup tables for error mappings. Note that the structure is not
       copied, and that it is hence essential that the array stays
       available and constant during the entire remaining runtime of the

       The mapping array should be put together with a series of
       SD_BUS_ERROR_MAP() macro invocations that take a literal name
       string and a (positive) errno-style error number. The last entry
       of the array should be an invocation of the SD_BUS_ERROR_MAP_END
       macro. The array should not be put together without use of these
       two macros.

       Note that the call is idempotent: it is safe to invoke it
       multiple times with the parameter, which will only add the passed
       mapping array once.

       Note that the memory allocated by this call is not intended to be
       freed during the lifetime of the process. It should not be freed

RETURN VALUE         top

       sd_bus_error_add_map() returns a positive value when the new
       array was added to the lookup tables. It returns zero when the
       same array was already added before. On error, a negative
       errno-style error code is returned. See below for known error

       Returned errors may indicate the following problems:

           The specified mapping array is invalid.

           Memory allocation failed.

NOTES         top

       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

HISTORY         top

       sd_bus_error_add_map() was added in version 223.

SEE ALSO         top

       systemd(1), sd-bus(3), sd_bus_error(3), sd-bus-errors(3),
       errno(3), strerror_r(3)

COLOPHON         top

       This page is part of the systemd (systemd system and service
       manager) project.  Information about the project can be found at
       ⟨⟩.  If you have
       a bug report for this manual page, see
       This page was obtained from the project's upstream Git repository
       ⟨⟩ on 2023-12-22.  (At that
       time, the date of the most recent commit that was found in the
       repository was 2023-12-22.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
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       (which is not part of the original manual page), send a mail to

systemd 255                                      SD_BUS_ERROR_ADD_MAP(3)

Pages that refer to this page: sd-bus(3)sd_bus_error(3)sd_bus_message_get_type(3)systemd.directives(7)systemd.index(7)