1SD_JOURNAL_GET_CURSOR(3)     sd_journal_get_cursor    SD_JOURNAL_GET_CURSOR(3)
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NAME

6       sd_journal_get_cursor, sd_journal_test_cursor - Get cursor string for
7       or test cursor string against the current journal entry
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SYNOPSIS

10       #include <systemd/sd-journal.h>
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12       int sd_journal_get_cursor(sd_journal *j, char **cursor);
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14       int sd_journal_test_cursor(sd_journal *j, const char *cursor);
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DESCRIPTION

17       sd_journal_get_cursor() returns a cursor string for the current journal
18       entry. A cursor is a serialization of the current journal position
19       formatted as text. The string only contains printable characters and
20       can be passed around in text form. The cursor identifies a journal
21       entry globally and in a stable way and may be used to later seek to it
22       via sd_journal_seek_cursor(3). The cursor string should be considered
23       opaque and not be parsed by clients. Seeking to a cursor position
24       without the specific entry being available locally will seek to the
25       next closest (in terms of time) available entry. The call takes two
26       arguments: a journal context object and a pointer to a string pointer
27       where the cursor string will be placed. The string is allocated via
28       libc malloc(3) and should be freed after use with free(3).
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30       Note that sd_journal_get_cursor() will not work before
31       sd_journal_next(3) (or related call) has been called at least once, in
32       order to position the read pointer at a valid entry.
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34       sd_journal_test_cursor() may be used to check whether the current
35       position in the journal matches the specified cursor. This is useful
36       since cursor strings do not uniquely identify an entry: the same entry
37       might be referred to by multiple different cursor strings, and hence
38       string comparing cursors is not possible. Use this call to verify after
39       an invocation of sd_journal_seek_cursor(3) whether the entry being
40       sought to was actually found in the journal or the next closest entry
41       was used instead.
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RETURN VALUE

44       sd_journal_get_cursor() returns 0 on success or a negative errno-style
45       error code.  sd_journal_test_cursor() returns positive if the current
46       entry matches the specified cursor, 0 if it does not match the
47       specified cursor or a negative errno-style error code on failure.
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NOTES

50       All functions listed here are thread-agnostic and only a single thread
51       may operate on a given sd_journal object.
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53       These APIs are implemented as a shared library, which can be compiled
54       and linked to with the libsystemd pkg-config(1) file.
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SEE ALSO

57       systemd(1), sd-journal(3), sd_journal_open(3),
58       sd_journal_seek_cursor(3)
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62systemd 239                                           SD_JOURNAL_GET_CURSOR(3)
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