DbEnv::set_tmp_dir

API Ref

#include <db_cxx.h>

int DbEnv::set_tmp_dir(const char *dir);

int DbEnv::get_tmp_dir(const char **dirp);


Description: DbEnv::set_tmp_dir

Specify the path of a directory to be used as the location of temporary files. The files created to back in-memory access method databases will be created relative to this path. These temporary files can be quite large, depending on the size of the database.

If no directories are specified, the following alternatives are checked in the specified order. The first existing directory path is used for all temporary files.

  1. The value of the environment variable TMPDIR.
  2. The value of the environment variable TEMP.
  3. The value of the environment variable TMP.
  4. The value of the environment variable TempFolder.
  5. The value returned by the GetTempPath interface.
  6. The directory /var/tmp.
  7. The directory /usr/tmp.
  8. The directory /temp.
  9. The directory /tmp.
  10. The directory C:/temp.
  11. The directory C:/tmp.

Note: environment variables are only checked if one of the DB_USE_ENVIRON or DB_USE_ENVIRON_ROOT flags were specified.

Note: the GetTempPath interface is only checked on Win/32 platforms.

The database environment's temporary file directory may also be set using the environment's DB_CONFIG file. The syntax of the entry in that file is a single line with the string "set_tmp_dir", one or more whitespace characters, and the directory name. Because the DB_CONFIG file is read when the database environment is opened, it will silently overrule configuration done before that time.

The DbEnv::set_tmp_dir method configures operations performed using the specified DbEnv handle, not all operations performed on the underlying database environment.

The DbEnv::set_tmp_dir method may not be called after the DbEnv::open method is called. If the database environment already exists when DbEnv::open is called, the information specified to DbEnv::set_tmp_dir must be consistent with the existing environment or corruption can occur.

The DbEnv::set_tmp_dir method either returns a non-zero error value or throws an exception that encapsulates a non-zero error value on failure, and returns 0 on success.

Parameters

dir
The dir parameter is the directory to be used to store temporary files.

On Windows, the dir argument will be interpreted as a UTF-8 string, which is equivalent to ASCII for Latin characters.

Errors

The DbEnv::set_tmp_dir method may fail and throw DbException, encapsulating one of the following non-zero errors, or return one of the following non-zero errors:

EINVAL
If the method was called after DbEnv::open was called; or if an invalid flag value or parameter was specified.

Description: DbEnv::get_tmp_dir

The DbEnv::get_tmp_dir method returns the database environment temporary file directory.

The DbEnv::get_tmp_dir method may be called at any time during the life of the application.

The DbEnv::get_tmp_dir method either returns a non-zero error value or throws an exception that encapsulates a non-zero error value on failure, and returns 0 on success.

Parameters

dirp
The DbEnv::get_tmp_dir method returns a reference to the database environment temporary file directory in dirp.

Class

DbEnv

See Also

Database Environments and Related Methods

APIRef

Copyright (c) 1996-2004 Sleepycat Software, Inc. - All rights reserved.