X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=man%2Fsd_bus_message_get_monotonic_usec.xml;h=42842116a0143219ce65ad6bb41ead0ba1d0155f;hp=57b115c63a028ac053f18514587b2e9918358fae;hb=61adca52f6f0b119e501c523008a454887cdf2b9;hpb=3736955368e8a3a24962f5fdd25cce3281885c30 diff --git a/man/sd_bus_message_get_monotonic_usec.xml b/man/sd_bus_message_get_monotonic_usec.xml index 57b115c63..42842116a 100644 --- a/man/sd_bus_message_get_monotonic_usec.xml +++ b/man/sd_bus_message_get_monotonic_usec.xml @@ -1,6 +1,6 @@ + "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> - - - - sd_bus_message_get_monotonic_usec - systemd - - - - Developer - Lennart - Poettering - lennart@poettering.net - - - - - - sd_bus_message_get_monotonic_usec - 3 - - - - sd_bus_message_get_monotonic_usec - sd_bus_message_get_realtime_usec - sd_bus_message_get_seqnum - Retrieve the sender timestamps and sequence number of a message - - - - - #include <systemd/sd-bus.h> - - - int sd_bus_message_get_monotonic_usec - sd_bus_message* message - uint64_t* usec - - - - int sd_bus_message_get_realtime_usec - sd_bus_message* message - uint64_t* usec - - - - int sd_bus_message_get_seqnum - sd_bus_message* message - uint64_t* seqnum - - - - - - Description - - sd_bus_message_get_monotonic_usec() - returns the monotonic timestamp of the time the - message was sent. This value is in microseconds since - the CLOCK_MONOTONIC epoch, see - clock_gettime2 - for details. - - Similar, - sd_bus_message_get_realtime_usec() - returns the realtime (wallclock) timestamp of the time - the message was sent. This value is in microseconds - since Jan 1st, 1970, i.e. in the - CLOCK_REALTIME clock. - - sd_bus_message_get_seqnum() - returns the kernel-assigned sequence number of the - message. The kernel assigns a global monotonically increasing - sequence number to all messages sent on the local - system. This sequence number is useful for determining - message send order, even across different busses of - the local system. The sequence number combined with - the boot ID of the system (as returned by - sd_id128_get_boot3) - is a suitable globally unique identifier for bus - messages. - - These timestamps and the sequence number are - attached to each message by the kernel and cannot be - manipulated by the sending userspace. - - Note that these timestamps are only available on - some bus transports, and only after support for them - has been negotiated with the - sd_bus_negotiate_timestamp3 - call. - - - - Return Value - - On success, these calls return 0 or a positive - integer. On failure, these calls return a negative - errno-style error code. - - On success, the timestamp or sequence number is - returned in the specified 64-bit unsigned integer - variable. - - - - Errors - - Returned errors may indicate the following problems: - - - - -EINVAL - - A specified parameter - is invalid. - - - - -ENODATA - - No timestamp or - sequence number information is - attached to the passed message. This - error is returned if the underlying - transport does not support - timestamping or assigning of sequence - numbers, or if this feature has not - been negotiated with - sd_bus_negotiate_timestamp3. - - - - - - Notes - - The - sd_bus_message_get_monotonic_usec(), - sd_bus_message_get_realtime_usec(), - and sd_bus_message_get_seqnum() - interfaces are available as a shared library, which - can be compiled and linked to with the - libsystemd pkg-config1 - file. - - - - See Also - - - systemd1, - sd-bus3, - sd_bus_new3, - sd_bus_negotiate_timestamp3, - clock_gettime2, - sd_id128_get_boot3 - - + + + + sd_bus_message_get_monotonic_usec + systemd + + + + Developer + Lennart + Poettering + lennart@poettering.net + + + + + + sd_bus_message_get_monotonic_usec + 3 + + + + sd_bus_message_get_monotonic_usec + sd_bus_message_get_realtime_usec + sd_bus_message_get_seqnum + Retrieve the sender timestamps and sequence number of a message + + + + + #include <systemd/sd-bus.h> + + + int sd_bus_message_get_monotonic_usec + sd_bus_message *message + uint64_t *usec + + + + int sd_bus_message_get_realtime_usec + sd_bus_message *message + uint64_t *usec + + + + int sd_bus_message_get_seqnum + sd_bus_message *message + uint64_t *seqnum + + + + + + Description + + sd_bus_message_get_monotonic_usec() + returns the monotonic timestamp of the time the message was sent. + This value is in microseconds since the + CLOCK_MONOTONIC epoch, see + clock_gettime2 + for details. + + Similar, + sd_bus_message_get_realtime_usec() returns + the realtime (wallclock) timestamp of the time the message was + sent. This value is in microseconds since Jan 1st, 1970, i.e. in + the CLOCK_REALTIME clock. + + sd_bus_message_get_seqnum() returns the + kernel-assigned sequence number of the message. The kernel assigns + a global, monotonically increasing sequence number to all messages + transmitted on the local system, at the time the message was sent. + This sequence number is useful for determining message send order, + even across different busses of the local system. The sequence + number combined with the boot ID of the system (as returned by + sd_id128_get_boot3) + is a suitable globally unique identifier for bus messages. + + Note that the sending order and receiving order of messages + might differ, in particular for broadcast messages. This means + that the sequence number and the timestamps of messages a client + reads are not necessarily monotonically increasing. + + These timestamps and the sequence number are attached to + each message by the kernel and cannot be manipulated by the + sender. + + Note that these timestamps are only available on some bus + transports, and only after support for them has been negotiated + with the + sd_bus_negotiate_timestamp3 + call. + + + + Return Value + + On success, these calls return 0 or a positive integer. On + failure, these calls return a negative errno-style error + code. + + On success, the timestamp or sequence number is returned in + the specified 64-bit unsigned integer variable. + + + + Errors + + Returned errors may indicate the following problems: + + + + -EINVAL + + A specified parameter is + invalid. + + + + -ENODATA + + No timestamp or sequence number information is + attached to the passed message. This error is returned if the + underlying transport does not support timestamping or + assigning of sequence numbers, or if this feature has not been + negotiated with + sd_bus_negotiate_timestamp3. + + + + + + Notes + + The + sd_bus_message_get_monotonic_usec(), + sd_bus_message_get_realtime_usec(), and + sd_bus_message_get_seqnum() interfaces are + available as a shared library, which can be compiled and linked to + with the + libsystemd pkg-config1 + file. + + + + See Also + + + systemd1, + sd-bus3, + sd_bus_new3, + sd_bus_negotiate_timestamp3, + clock_gettime2, + sd_id128_get_boot3 + +