2 .TH "SD_JOURNAL_GET_CURSOR" "3" "" "systemd 220" "sd_journal_get_cursor"
3 .\" -----------------------------------------------------------------
4 .\" * Define some portability stuff
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6 .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
7 .\" http://bugs.debian.org/507673
8 .\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html
9 .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
12 .\" -----------------------------------------------------------------
13 .\" * set default formatting
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15 .\" disable hyphenation
17 .\" disable justification (adjust text to left margin only)
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20 .\" * MAIN CONTENT STARTS HERE *
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23 sd_journal_get_cursor, sd_journal_test_cursor \- Get cursor string for or test cursor string against the current journal entry
28 #include <systemd/sd\-journal\&.h>
31 .HP \w'int\ sd_journal_get_cursor('u
32 .BI "int sd_journal_get_cursor(sd_journal\ *" "j" ", char\ **" "cursor" ");"
33 .HP \w'int\ sd_journal_test_cursor('u
34 .BI "int sd_journal_test_cursor(sd_journal\ *" "j" ", const\ char\ *" "cursor" ");"
37 \fBsd_journal_get_cursor()\fR
38 returns a cursor string for the current journal entry\&. A cursor is a serialization of the current journal position formatted as text\&. The string only contains printable characters and can be passed around in text form\&. The cursor identifies a journal entry globally and in a stable way and may be used to later seek to it via
39 \fBsd_journal_seek_cursor\fR(3)\&. The cursor string should be considered opaque and not be parsed by clients\&. Seeking to a cursor position without the specific entry being available locally will seek to the next closest (in terms of time) available entry\&. The call takes two arguments: a journal context object and a pointer to a string pointer where the cursor string will be placed\&. The string is allocated via libc
41 and should be freed after use with
45 \fBsd_journal_get_cursor()\fR
47 \fBsd_journal_next\fR(3)
48 (or related call) has been called at least once, in order to position the read pointer at a valid entry\&.
50 \fBsd_journal_test_cursor()\fR
51 may be used to check whether the current position in the journal matches the specified cursor\&. This is useful since cursor strings do not uniquely identify an entry: the same entry might be referred to by multiple different cursor strings, and hence string comparing cursors is not possible\&. Use this call to verify after an invocation of
52 \fBsd_journal_seek_cursor\fR(3)
53 whether the entry being sought to was actually found in the journal or the next closest entry was used instead\&.
56 \fBsd_journal_get_cursor()\fR
57 returns 0 on success or a negative errno\-style error code\&.
58 \fBsd_journal_test_cursor()\fR
59 returns positive if the current entry matches the specified cursor, 0 if it does not match the specified cursor or a negative errno\-style error code on failure\&.
63 \fBsd_journal_get_cursor()\fR
65 \fBsd_journal_test_cursor()\fR
66 interfaces are available as a shared library, which can be compiled and linked to with the
67 \fBlibsystemd\fR\ \&\fBpkg-config\fR(1)
73 \fBsd_journal_open\fR(3),
74 \fBsd_journal_seek_cursor\fR(3)