### Modifying Hostdata

Changing hostdata cannot only change the way the host works but it also affects other files and processes on the host. Therefore, care should be taken when changing hostdata. Deleting the well-known hostdata entries can cause even more serious operational problems for the host.

The current as well as earlier versions of DCE provide configuration routines that use a dce_cf.db file for data. When hostdata changes, dced also makes the appropriate changes to this file so that the dce_cf* routines continue to work correctly. This is one reason the hostdata items are established as well-known names with well-known UUIDs so that dced knows which values to monitor.

Management applications use the dced_hostdata_read( ) routine to obtain the data for an entry referred to by an entry UUID. To modify an entry's actual data, applications use the dced_hostdata_write( ) routine. This routine replaces the old data with the new data for the hostdata entry represented by the entry UUID. The hostdata entry must already exist because this routine will not create it. Use the dced_hostdata_create( ) routine to create new hostdata entries.

###