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sd_journal_has_runtime_files(3) — Linux manual page

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

SD_JOURN...ME_FILES(3) sd_journal_has_runtime_filesSD_JOURN...ME_FILES(3)

NAME         top

       sd_journal_has_runtime_files, sd_journal_has_persistent_files -
       Query availability of runtime or persistent journal files

SYNOPSIS         top

       #include <systemd/sd-journal.h>

       int sd_journal_has_runtime_files(sd_journal *j);

       int sd_journal_has_persistent_files(sd_journal *j);

DESCRIPTION         top

       sd_journal_has_runtime_files() returns a positive value if runtime
       journal files (present in /run/systemd/journal/) have been found.
       Otherwise, returns 0.

       sd_journal_has_persistent_files() returns a positive value if
       persistent journal files (present in /var/log/journal/) have been
       found. Otherwise, returns 0.

RETURN VALUE         top

       Both sd_journal_has_runtime_files() and
       sd_journal_has_persistent_files() return -EINVAL if their argument
       is NULL.

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_has_runtime_files() and
       sd_journal_has_persistent_files() were added in version 229.

SEE ALSO         top

       systemd(1), sd-journal(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
       ⟨http://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_JOURN...ME_FILES(3)

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

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