sd_bus_message_set_expect_reply

elogind
sd_bus_message_set_expect_reply 3
sd_bus_message_set_expect_reply sd_bus_message_get_expect_reply sd_bus_message_set_auto_start sd_bus_message_get_auto_start sd_bus_message_set_allow_interactive_authorization sd_bus_message_get_allow_interactive_authorization Set and query bus message metadata

    #include <elogind/sd-bus.h>

int `sd_bus_message_set_expect_reply` sd_bus_message *message int b int `sd_bus_message_get_expect_reply` sd_bus_message *message int `sd_bus_message_set_auto_start` sd_bus_message *message int b int `sd_bus_message_get_auto_start` sd_bus_message *message int `sd_bus_message_set_allow_interactive_authorization` sd_bus_message *message int b int `sd_bus_message_get_allow_interactive_authorization` sd_bus_message *message

## Description

`sd_bus_message_set_expect_reply()` sets or clears the `NO_REPLY_EXPECTED` flag on the message m. This flag matters only for method call messages and is used to specify that no method return or error reply is expected. It is ignored for other types. Thus, for a method call message, calling

    sd_bus_message_set_expect_reply(…, 0)

sets the flag and suppresses the reply.

`sd_bus_message_get_expect_reply()` checks if the `NO_REPLY_EXPECTED` flag is set on the message m. It will return positive if it is not set, and zero if it is.

`sd_bus_message_set_auto_start()` sets or clears the `NO_AUTO_START` flag on the message m. When the flag is set, the bus must not launch an owner for the destination name in response to this message. Calling

    sd_bus_message_set_auto_start(…, 0)

sets the flag.

`sd_bus_message_get_auto_start()` checks if the `NO_AUTO_START` flag is set on the message m. It will return positive if it is not set, and zero if it is.

`sd_bus_message_set_allow_interactive_authorization()` sets or clears the `ALLOW_INTERACTIVE_AUTHORIZATION` flag on the message m. Setting this flag informs the receiver that the caller is prepared to wait for interactive authorization via polkit or a similar framework. Note that setting this flag does not guarantee that the receiver will actually perform interactive authorization. Also, make sure to set a suitable message timeout when using this flag since interactive authorization could potentially take a long time as it depends on user input. If b is non-zero, the flag is set.

`sd_bus_message_get_allow_interactive_authorization()` checks if the `ALLOW_INTERACTIVE_AUTHORIZATION` flag is set on the message m. It will return a positive integer if the flag is set. Otherwise, it returns zero.

## Return Value

On success, these functions return a non-negative integer. On failure, they return a negative errno-style error code.

### Errors

Returned errors may indicate the following problems:

`-EINVAL`

  The message parameter is `NULL`.

`-EPERM`

  The message message is sealed when trying to set a flag.

  The message message has wrong type.

## History

`sd_bus_message_set_expect_reply()`, `sd_bus_message_get_expect_reply()`, `sd_bus_message_set_auto_start()`, and `sd_bus_message_get_auto_start()` were added in version 240.

`sd_bus_message_set_allow_interactive_authorization()` and `sd_bus_message_get_allow_interactive_authorization()` were added in version 246.

## See Also

elogind 8, sd-bus 3, sd_bus_set_description 3