#include <db_cxx.h> int DbEnv::set_intermediate_dir_mode(u_int32_t mode);
By default, Berkeley DB does not create intermediate directories needed for recovery, that is, if the file /a/b/c/mydatabase is being recovered, and the directory path b/c does not exist, recovery will fail. This default behavior is because Berkeley DB does not know what permissions are appropriate for intermediate directory creation, and creating the directory might result in a security problem.
The DbEnv::set_intermediate_dir_mode() method causes Berkeley DB to
create any intermediate directories needed during recovery, using the
specified permissions.
On UNIX systems or in IEEE/ANSI Std 1003.1 (POSIX) environments, created directories are owned by the process owner; the group ownership of created directories is based on the system and directory defaults, and is not further specified by Berkeley DB.
The database environment's intermediate directory permissions may also be configured using the environment's DB_CONFIG file. The syntax of the entry in that file is a single line with the string "set_intermediate_dir_mode", one or more whitespace characters, and the directory permissions. 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_intermediate_dir_mode() method configures operations
performed using the specified
DbEnv handle, not all
operations performed on the underlying database environment.
The DbEnv::set_intermediate_dir_mode() method may not be called
after the
DbEnv::open()
method is called.
The DbEnv::set_intermediate_dir_mode()
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.
The mode parameter specifies the directory permissions.
Directory permissions are interpreted as a string of nine characters, using the character set r (read), w (write), x (execute or search), and - (none). The first character is the read permissions for the directory owner (set to either r or -). The second character is the write permissions for the directory owner (set to either w or -). The third character is the execute permissions for the directory owner (set to either x or -).
Similarly, the second set of three characters are the read, write and execute/search permissions for the directory group, and the third set of three characters are the read, write and execute/search permissions for all others. For example, the string rwx------ would configure read, write and execute/search access for the owner only. The string rwxrwx--- would configure read, write and execute/search access for both the owner and the group. The string rwxr----- would configure read, write and execute/search access for the directory owner and read-only access for the directory group.
The DbEnv::set_intermediate_dir_mode()
method may fail and throw a DbException
exception, encapsulating one of the following non-zero errors, or return one
of the following non-zero errors:
If the method was called after DbEnv::open() was called; or if an invalid flag value or parameter was specified.