Library Version 18.1.40

DB_LOGC->get()
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## DB_LOGC->get()

    #include <db.h>

    int
    DB_LOGC->get(DB_LOGC *logc, DB_LSN *lsn, DBT *data, u_int32_t flags);

The `DB_LOGC->get()` method returns records from the log.

Unless otherwise specified, the `DB_LOGC->get()` method returns a non-zero error value on failure and 0 on success.

### Parameters

#### lsn

When the flag parameter is set to DB_CURRENT, DB_FIRST, DB_LAST, DB_NEXT or DB_PREV, the lsn parameter is overwritten with the DB_LSN value of the record retrieved. When flag is set to DB_SET, the lsn parameter is the DB_LSN value of the record to be retrieved.

#### data

The data field of the data structure is set to the record retrieved, and the size field indicates the number of bytes in the record. See DBT for a description of other fields in the data structure. The DB_DBT_MALLOC, DB_DBT_REALLOC and DB_DBT_USERMEM flags may be specified for any DBT used for data retrieval.

#### flags

The flags parameter must be set to one of the following values:

- `DB_CURRENT`

  Return the log record to which the log currently refers.

- `DB_FIRST`

  The first record from any of the log files found in the log directory is returned in the data parameter. The lsn parameter is overwritten with the DB_LSN of the record returned.

  The `DB_LOGC->get()` method will return DB_NOTFOUND if DB_FIRST is set and the log is empty.

- `DB_LAST`

  The last record in the log is returned in the data parameter. The lsn parameter is overwritten with the DB_LSN of the record returned.

  The `DB_LOGC->get()` method will return DB_NOTFOUND if DB_LAST is set and the log is empty.

- `DB_NEXT`

  The current log position is advanced to the next record in the log, and that record is returned in the data parameter. The lsn parameter is overwritten with the DB_LSN of the record returned.

  If the cursor has not been initialized via DB_FIRST, DB_LAST, DB_SET, DB_NEXT, or DB_PREV, `DB_LOGC->get()` will return the first record in the log.

  The `DB_LOGC->get()` method will return DB_NOTFOUND if DB_NEXT is set and the last log record has already been returned or the log is empty.

- `DB_PREV`

  The current log position is advanced to the previous record in the log, and that record is returned in the data parameter. The lsn parameter is overwritten with the DB_LSN of the record returned.

  If the cursor has not been initialized via DB_FIRST, DB_LAST, DB_SET, DB_NEXT, or DB_PREV, `DB_LOGC->get()` will return the last record in the log.

  The `DB_LOGC->get()` method will return DB_NOTFOUND if DB_PREV is set and the first log record has already been returned or the log is empty.

- `DB_SET`

  Retrieve the record specified by the lsn parameter.

### Errors

The `DB_LOGC->get()` method may fail and return one of the following non-zero errors:

#### EINVAL

If the DB_CURRENT flag was set and the log cursor has not yet been initialized; the DB_CURRENT, DB_NEXT, or DB_PREV flags were set and the log was opened with the DB_THREAD flag set; the DB_SET flag was set and the specified log sequence number does not appear in the log; or if an invalid flag value or parameter was specified.

### Class

DB_ENV, DB_LOGC, DB_LSN

### See Also

Logging Subsystem and Related Methods

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