DAM file service functions (dc_dam_~) can be used to access TAM file records. In this case, a logical file name used for a DAM file is regarded as a TAM table name. A relative block number used for a DAM file is regarded as a TAM table key value. The following DAM service functions can be used to access TAM files:

• dc_dam_open() (Opens logical files.)
• dc_dam_close() (Closes logical files.)
• dc_dam_read() (Inputs logical file blocks.)
• dc_dam_rewrite() (Updates logical file blocks.)
• dc_dam_write() (Outputs logical file blocks.)

When the function dc_dam_hold() (which shuts down logical files) or the function dc_dam_release() (which releases logical files from the shutdown state) is issued for a TAM file, the function returns normally. However, the TAM file is not actually shut down or released from the shutdown state.

The following DAM service functions cannot be used to access TAM file records:

• All functions used for any job in offline mode
• dc_dam_start() (Start using an unrecoverable DAM file)
• dc_dam_end() (Terminate using an unrecoverable DAM file)
• dc_dam_status() (Reference the status of a logical file)

To enable TAM access for a DAM file, change the file as explained below:

1. Enter the DAM file data with the function dc_dam_get(), give a key value to each data item, then store the data times in any file.
2. Enter the file in 1, and execute the tamcre command to create a TAM file.