1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
|
'\" t
.TH "SD_BUS_IS_OPEN" "3" "" "systemd 241" "sd_bus_is_open"
.\" -----------------------------------------------------------------
.\" * Define some portability stuff
.\" -----------------------------------------------------------------
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.\" http://bugs.debian.org/507673
.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.ie \n(.g .ds Aq \(aq
.el .ds Aq '
.\" -----------------------------------------------------------------
.\" * set default formatting
.\" -----------------------------------------------------------------
.\" disable hyphenation
.nh
.\" disable justification (adjust text to left margin only)
.ad l
.\" -----------------------------------------------------------------
.\" * MAIN CONTENT STARTS HERE *
.\" -----------------------------------------------------------------
.SH "NAME"
sd_bus_is_open, sd_bus_is_ready \- Check whether the a bus connection is open or ready\&.
.SH "SYNOPSIS"
.sp
.ft B
.nf
#include <systemd/sd\-bus\&.h>
.fi
.ft
.HP \w'int\ sd_bus_is_open('u
.BI "int sd_bus_is_open(sd_bus\ *" "bus" ");"
.HP \w'int\ sd_bus_is_ready('u
.BI "int sd_bus_is_ready(sd_bus\ *" "bus" ");"
.SH "DESCRIPTION"
.PP
\fBsd_bus_is_open()\fR
checks whether the specified bus connection is open, i\&.e\&. in the process of being established, already established or in the process of being torn down\&. It returns zero when the connection has not been started yet (i\&.e\&.
\fBsd_bus_start\fR(3)
or some equivalent call has not been invoked yet), or is fully terminated again (for example after
\fBsd_bus_close\fR(3)), it returns positive otherwise\&.
.PP
\fBsd_bus_is_ready()\fR
checks whether the specified connection is fully established, i\&.e\&. completed the connection and authentication phases of the protocol and received the
\fBHello()\fR
method call response, and is not in the process of being torn down again\&. It returns zero outside of this state, and positive otherwise\&. Effectively, this function returns positive while regular messages can be sent or received on the connection\&.
.PP
To be notified when the connection is fully established, use
\fBsd_bus_set_connected_signal\fR(3)
and install a match for the
\fBConnected()\fR
signal on the
"org\&.freedesktop\&.DBus\&.Local"
interface\&. To be notified when the connection is torn down again, install a match for the
\fBDisconnected()\fR
signal on the
"org\&.freedesktop\&.DBus\&.Local"
interface\&.
.SH "RETURN VALUE"
.PP
On success, these functions return 0 or a positive integer\&. On failure, they return a negative errno\-style error code\&.
.SH "ERRORS"
.PP
Returned errors may indicate the following problems:
.PP
\fB\-ECHILD\fR
.RS 4
The bus connection has been created in a different process\&.
.RE
.SH "NOTES"
.PP
These APIs are implemented as a shared library, which can be compiled and linked to with the
\fBlibsystemd\fR\ \&\fBpkg-config\fR(1)
file\&.
.SH "SEE ALSO"
.PP
\fBsystemd\fR(1),
\fBsd-bus\fR(3),
\fBsd_bus_start\fR(3),
\fBsd_bus_close\fR(3),
\fBsd_bus_set_connected_signal\fR(3)
|
