# DB_MPOOLFILE->set_clear_len

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    #include <db.h>

    int
    DB_MPOOLFILE->set_clear_len(DB_MPOOLFILE *mpf, u_int32_t len);

# Description

The DB_MPOOLFILE->set_clear_len method sets the number of initial bytes in a page that should be set to nul when the page is created as a result of the DB_MPOOL_CREATE or DB_MPOOL_NEW flags being specified to DB_MPOOLFILE->get. If no value is specified, or len is 0, the entire page is cleared.

The DB_MPOOLFILE->set_clear_len method configures a file in the memory pool, not only operations performed using the specified DB_MPOOLFILE handle.

The DB_MPOOLFILE->set_clear_len interface may not be called after the DB_MPOOLFILE->open interface is called. If the file is already open in the memory pool when DB_MPOOLFILE->open is called, the information specified to DB_MPOOLFILE->set_clear_len must be consistent with the existing file or an error will be returned.

The DB_MPOOLFILE->set_clear_len method returns a non-zero error value on failure and 0 on success.

# Errors

The DB_MPOOLFILE->set_clear_len method may fail and return a non-zero error for errors specified for other Berkeley DB and C library or system functions. If a catastrophic error has occurred, the DB_MPOOLFILE->set_clear_len method may fail and return DB_RUNRECOVERY, in which case all subsequent Berkeley DB calls will fail in the same way.

# Class

DB_ENV, DB_MPOOLFILE

# See Also

Memory Pools and Related Methods`

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