1SD_BUS_MESSAGE_GET_SIGNATUsRdE_(b3u)s_message_get_signSaDt_uBrUeS_MESSAGE_GET_SIGNATURE(3)
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NAME

6       sd_bus_message_get_signature, sd_bus_message_is_empty,
7       sd_bus_message_has_signature - Query bus message signature
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SYNOPSIS

10       #include <systemd/sd-bus.h>
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12       const char* sd_bus_message_get_signature(sd_bus_message *message,
13                                                int complete);
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15       int sd_bus_message_is_empty(sd_bus_message *message);
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17       int sd_bus_message_has_signature(sd_bus_message *message,
18                                        const char *signature);
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DESCRIPTION

21       sd_bus_message_get_signature() returns the signature of message
22       message. If complete is true, the signature of the whole message is
23       returned, and just the signature of the currently open container
24       otherwise.
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26       sd_bus_message_is_empty() returns true if the message is empty, i.e.
27       when its signature is empty.
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29       sd_bus_message_has_signature() returns true if the signature of the
30       message message matches given signature. Parameter signature may be
31       NULL, this is treated the same as an empty string, which is equivalent
32       to calling sd_bus_message_is_empty().
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RETURN VALUE

35       On success, sd_bus_message_get_signature() returns the signature, and
36       NULL on error.
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38       The other functions return 0 or a positive integer on success. On
39       failure, they return a negative errno-style error code.
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41   Errors
42       Returned errors may indicate the following problems:
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44       -EINVAL
45           The message parameter is NULL.
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47       NULL
48           The message parameter is NULL.
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NOTES

51       Functions described here are available as a shared library, which can
52       be compiled against and linked to with the libsystemd pkg-config(1)
53       file.
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55       The code described here uses getenv(3), which is declared to be not
56       multi-thread-safe. This means that the code calling the functions
57       described here must not call setenv(3) from a parallel thread. It is
58       recommended to only do calls to setenv() from an early phase of the
59       program when no other threads have been started.
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SEE ALSO

62       systemd(1), sd-bus(3), sd_bus_message_new(3)
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66systemd 254                                    SD_BUS_MESSAGE_GET_SIGNATURE(3)
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