mi_scan_setuserdata()

void mi_scan_setuserdata(MI_AM_SCAN_DESC *scanDesc, void
*userdata);

scanDesc: points to the scan descriptor.
user_data: points to the user data.

The access method can create a user-data structure in shared memory to store reusable information, such as function descriptors for qualifications and to maintain a row pointer for each execution of the am_getnext purpose function. To retain user data in memory during the scan (starting when am_beginscan is called and ending when am_endscan is called), follow these steps:

To retain user data in memory during the scan

In the am_beginscan purpose function, call the appropriate DataBlade API function to allocate memory for the user-data structure.
Allocate the user-data memory with a duration of PER_COMMAND.
In am_getnext, populate the user-data structure with scan-state information.
Before am_getnext exits, call mi_scan_setuserdata() to store a pointer to the user-data structure in the scan descriptor.
In the am_endscan purpose function, call the appropriate DataBlade API function to deallocate the user-data memory.

None

See the descriptions of:

Function mi_scan_userdata()
DataBlade API functions for memory allocation and duration in Storing Data in Shared Memory

mi_scan_setuserdata()

Syntax

Usage

Return Values

Related Topics