ActiveTcl User Guide
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ActiveTcl User Guide
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xotcl/library/store/Storage.xotcl| Description: | Simple generic storage interface for hashtable-like (persistent) storages. There are several different existing stores, including a memory storage, a GDBM storage, a SDBM storage, and a TextFile storage. |
| Date: | $Date: 2004/05/23 22:50:39 $ |
| Description: | Abstract storage interface class (superclass of all storages). |
| Arguments: | filename: database filename (or filename base, if more than one file has to be created) |
| Description: | Each storage object represents exactly one database table. The db has to be opened, before it can it used. If it is not opened all other methods return errors. |
| Return: | empty string |
| Description: | Close associated database. |
| Return: | empty string |
| Arguments: | key: Key to be searched for. |
| Description: | Search for a key whether it exists or not. |
| Return: | 1, if key exists in the database, otherwise 0 |
| Arguments: | key: Key to be set. |
| ?value?: Optional value that might be set | |
| Description: | Set or query a database key in the same way as Tcl's set functions. |
| Return: | Key value. |
| Arguments: | key: Key to be unset. |
| Description: | Unset a database key in the same way as Tcl's unset functions. |
| Return: | empty string |
| Description: | Return a list of keys in the database (functions in the same way as Tcl's array names) |
| Return: | List of keys in the db. |
| Description: | Start a traversal of the database, starting with any key. |
| Return: | Name of first key. |
| Description: | Proceed with the db traversal. Requires a firstkey before first usage, otherwise it returns an error. |
| Return: | Name of next key, if one exists. Otherwise an empty string is returned. |
| Description: | Create a childStore according to a preference list depending on which storages are available. Currently the preference list has the following order: Gdbm, Sdbm and TextFile. |
| Return: | name of the created storage object. |