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NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | NOTES | SEE ALSO | NOTES | COLOPHON |
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SD_BUS..._MEMFD(3) sd_bus_message_append_string_memfd SD_BUS..._MEMFD(3)
sd_bus_message_append_string_memfd,
sd_bus_message_append_string_iovec,
sd_bus_message_append_string_space - Attach a string to a message
#include <systemd/sd-bus.h>
int sd_bus_message_append_string_memfd(sd_bus_message *m,
int memfd);
int sd_bus_message_append_string_iovec(sd_bus_message *m,
const struct iovec *iov,
unsigned n);
int sd_bus_message_append_string_space(sd_bus_message *m,
size_t size, char **s);
The functions sd_bus_message_append_string_memfd() and
sd_bus_message_append_string_iovec() can be used to append a
single string (item of type "s") to message m.
In case of sd_bus_message_append_string_memfd(), the contents of
memfd are the string. They must satisfy the same constraints as
described for the "s" type in sd_bus_message_append_basic(3).
In case of sd_bus_message_append_string_iovec(), the payload of
iov is the string. It must satisfy the same constraints as
described for the "s" type in sd_bus_message_append_basic(3).
The iov argument must point to n struct iovec structures. Each
structure may have the iov_base field set, in which case the
memory pointed to will be copied into the message, or unset, in
which case a block of spaces (ASCII 32) of length iov_len will be
inserted. The memory pointed at by iov may be changed after this
call.
The sd_bus_message_append_string_space() function appends space
for a string to message m. It behaves similar to
sd_bus_message_append_basic() with type "s", but instead of
copying a string into the message, it returns a pointer to the
destination area to the caller in pointer p. Space for the string
of length size plus the terminating NUL is allocated.
On success, those calls return 0 or a positive integer. On
failure, they return a negative errno-style error code.
Errors
Returned errors may indicate the following problems:
-EINVAL
Specified parameter is invalid.
-EPERM
Message has been sealed.
-ESTALE
Message is in invalid state.
-ENXIO
Message cannot be appended to.
-ENOMEM
Memory allocation failed.
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
started.
systemd(1), sd-bus(3), sd_bus_message_append_basic(3), The D-Bus
specification[1]
1. The D-Bus specification
https://dbus.freedesktop.org/doc/dbus-specification.html
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 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 is not part of the original manual page), send a mail to
man-pages@man7.org
systemd 258~rc2 SD_BUS..._MEMFD(3)
Pages that refer to this page: sd-bus(3), systemd.directives(7), systemd.index(7)
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HTML rendering created 2025-09-06 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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