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Name

sd_bus_message_append_string_memfd, sd_bus_message_append_string_iovec, sd_bus_message_append_string_space — Attach a string to a message

Synopsis

#include <systemd/sd-bus.h>
int sd_bus_message_append_string_memfd(sd_bus_message *m,
 sd_memfd *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);
 

Description

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).

Pointer iov 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.

Function sd_bus_message_append_string_space appends space for a string to message m. If behaves similarly to sd_bus_message_append_basic with type "s", but instead of copying a string into the the message, it returns a pointer to the destination area to the caller in pointer p. Space for string of length size plus the terminating NUL is allocated.

Return Value

On success, those calls return 0 or a positive integer. On failure, they returns 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.

Notes

Functions described here are available as a shared library, which can be compiled and linked to with the libsystemd pkg-config(1) file.

See Also

systemd(1), sd-bus(3), sd_bus_message_append_basic(3), The D-Bus specification