llapi_changelog_clear(3)

LLAPI_CHANGELOG_CLEAR(3)

Lustre Library Functions

LLAPI_CHANGELOG_CLEAR(3)

NAME

llapi_changelog_clear - Clear changelog records for a changelog consumer

SYNOPSIS

#include <lustre/lustreapi.h>

int llapi_changelog_clear(const char *mdtname, const char *idstr,
                          long long endrec);

The function llapi_changelog_clear() indicates that changelog records previous to endrec are no longer of interest to a particular consumer idstr , potentially allowing the MDT mdtname (e.g: "lustrefs-MDT0000") to free up disk space by freeing old records if no other changelog consumers still need to process them.

An endrec of 0 indicates the current last record.

Changelog consumers must be registered on the MDT node using:
lctl --device MDT_NAME changelog_register

RETURN VALUES

Return the file descriptor on success or a negative errno value on failure.

ERRORS

-EINVAL: One or more invalid arguments are given.
-ENOENT: MDT's changelog char device or changelog user not found.
-ENOPERM: Not enough permissions to open the changelog char device. By default, the device is only accessible to the root user.

EXAMPLE

To clear the changelog for a specific consumer ID:



        char *mdtname = "testfs-MDT0000";


        char *idstr = "cl2-dirwatch";


        long long end_record = 12345678;


        rc = llapi_changelog_clear(mdtname, idstr, end_record);

AVAILABILITY

llapi_changelog_clear() is part of the lustre(7) user application interface library since release 2.0.0.