Berkeley DB: DbMpoolFile::put
Полезная информация

DbMpoolFile::put


#include <db_cxx.h>

int DbMpoolFile::put(void *pgaddr, u_int32_t flags);

Description

The DbMpoolFile::put method indicates that the page referenced by pgaddr can be evicted from the pool. The pgaddr argument must be an address previously returned by DbMpoolFile::get.

The flags argument is specified by logically OR'ing together one or more of the following values:

DB_MPOOL_CLEAN
Clear any previously set modification information (i.e., don't bother writing the page back to the source file).

DB_MPOOL_DIRTY
The page has been modified and must be written to the source file before being evicted from the pool.

DB_MPOOL_DISCARD
The page is unlikely to be useful in the near future, and should be discarded before other pages in the pool.

The DB_MPOOL_CLEAN and DB_MPOOL_DIRTY flags are mutually exclusive.

The DbMpoolFile::put method either returns errno or throws an exception that encapsulates an errno on failure, and 0 on success.

Errors

If a fatal error occurs in Berkeley DB, the DbMpoolFile::put method may fail and either return DB_RUNRECOVERY or throw an exception encapsulating DB_RUNRECOVERY, at which point all subsequent database calls will also fail in the same way. Methods marked as returning errno will, by default, throw an exception that encapsulates the error information. The default error behavior can be changed, see
DbException.

The DbMpoolFile::put method may fail and throw an exception for any of the errors specified for the following Berkeley DB and C library functions: DBmemp->pgin(3), DBmemp->pgout(3), abort(3), close(3), dbenv->db_paniccall(3), fcntl(3), fflush(3), fprintf(3), free(3), fstat(3), fsync(3), getenv(3), getpid(3), getuid(3), isdigit(3), DbLog::compare, DbLog::flush, lseek(3), malloc(3), memcmp(3), memcpy(3), memset(3), mmap(3), open(3), pread(3), pstat_getdynamic(3), pwrite(3), read(3), sigfillset(3), sigprocmask(3), stat(3), strerror(3), strlen(3), sysconf(3), time(3), unlink(3), vfprintf(3), vsnprintf(3), and write(3).

In addition, the DbMpoolFile::put method may fail and throw an exception or return errno for the following conditions:

EACCES
The DB_MPOOL_DIRTY flag was set and the source file was not opened for writing.

EINVAL
An invalid flag value or parameter was specified.

The pgaddr parameter does not reference a page returned by DbMpoolFile::get.

More than one of DB_MPOOL_CLEAN and DB_MPOOL_DIRTY flags was set.

Class

DbMpoolFile

See Also

DbMpoolFile::close, DbMpoolFile::get, DbMpoolFile::open, DbMpoolFile::put, DbMpoolFile::set and DbMpoolFile::sync.