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sd_journal_get_usage(3) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | NOTES | HISTORY | SEE ALSO | COLOPHON 

SD_JOURNAL_GET_USAGE(3)    sd_journal_get_usage   SD_JOURNAL_GET_USAGE(3)

NAME         top

       sd_journal_get_usage - Journal disk usage

SYNOPSIS         top

       #include <systemd/sd-journal.h>

       int sd_journal_get_usage(sd_journal *j, uint64_t *bytes);

DESCRIPTION         top

       sd_journal_get_usage() determines the total disk space currently
       used by journal files (in bytes). If SD_JOURNAL_LOCAL_ONLY was
       passed when opening the journal, this value will only reflect the
       size of journal files of the local host, otherwise of all hosts.

RETURN VALUE         top

       sd_journal_get_usage() returns 0 on success or a negative
       errno-style error code.

NOTES         top

       All functions listed here are thread-agnostic and only a single
       specific thread may operate on a given object during its entire
       lifetime. It is safe to allocate multiple independent objects and
       use each from a specific thread in parallel. However, it is not
       safe to allocate such an object in one thread, and operate or free
       it from any other, even if locking is used to ensure these threads
       do not operate on it at the very same time.

       Functions described here are available as a shared library, which
       can be compiled against and linked to with the
       libsystemd pkg-config(1) file.

HISTORY         top

       sd_journal_get_usage() was added in version 190.

SEE ALSO         top

       systemd(1), sd-journal(3), sd_journal_open(3)

COLOPHON         top

       This page is part of the systemd (systemd system and service
       manager) project.  Information about the project can be found at
       ⟨http://www.freedesktop.org/wiki/Software/systemd⟩.  If you have a
       bug report for this manual page, see
       ⟨http://www.freedesktop.org/wiki/Software/systemd/#bugreports⟩.
       This page was obtained from the project's upstream Git repository
       ⟨https://github.com/systemd/systemd.git⟩ on 2025-08-11.  (At that
       time, the date of the most recent commit that was found in the
       repository was 2025-08-11.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there is
       a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

systemd 258~rc2                                   SD_JOURNAL_GET_USAGE(3)

Pages that refer to this page: sd-journal(3),  systemd.directives(7),  systemd.index(7)

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