Allocates a CS_BLKDESC structure.
CS_RETCODE blk_alloc(connection, version, blk_pointer) CS_CONNECTION *connection; CS_INT version; CS_BLKDESC **blk_pointer;
A pointer to a CS_CONNECTION structure that has been allocated with ct_con_alloc and opened with ct_connect. A CS_CONNECTION structure contains information about a particular client/server connection.
The connection must not have any pending results.
The intended version of Bulk-Library behavior. During initialization, version’s value is checked for compatibility with Client-Library’s version level. version can take the following values:
Value |
Meaning |
Compatible Client-Library version level(s) |
|---|---|---|
BLK_VERSION_100 |
Version 10.0 behavior |
CS_VERSION_110, CS_VERSION_100 |
BLK_VERSION_110 |
Version 11.0 behavior |
Same as BLK_VERSION_100 |
BLK_VERSION_120 |
Version 12.0 behavior |
Same as BLK_VERSION_100, 110 |
BLK_VERSION_125 |
Version 12.5 behavior |
Same as BLK_VERSION_100, 110, 120 |
BLK_VERSION_150 |
Version 15.0 behavior |
Same as BLK_VERSION_100, 110, 120, 125 |
BLK_VERSION_100 can
only be used with Open Client and Open Server versions 11.x and
higher, regardless of whether the context/ctlib is initialized
to CS_VERSION_100 or CS_VERSION_110.
The application’s Client-Library version level is determined by the call to ct_init that initializes the connection’s parent context structure.
The address of a pointer variable. blk_alloc sets *blk_pointer to the address of a newly allocated CS_BLKDESC structure.
In case of error, blk_alloc sets *blk_pointer to NULL.
blk_alloc returns:
Returns |
Indicates |
|---|---|
CS_SUCCEED |
The routine completed successfully. |
CS_FAIL |
The routine failed. |
The most common reason for a blk_alloc failure is a lack of adequate memory.
/*
** BulkCopyIn()
** Ex_tabname is globally defined.
*/
CS_STATIC CS_RETCODE
BulkCopyIn(connection)
CS_CONNECTION *connection;
{
CS_BLKDESC *blkdesc;
CS_DATAFMT datafmt; /* variable descriptions */
Blk_Data *dptr; /* data for transfer */
CS_INT datalen[5]; /* variable data length */
CS_INT len;
CS_INT numrows;
/*
** Ready to start the bulk copy in now that all the
** connections have been made and have a table name.
** Start by getting the bulk descriptor and
** initializing.
*/
if (blk_alloc(connection, BLK_VERSION_100, &blkdesc)
!= CS_SUCCEED)
{
ex_error("BulkCopyIn: blk_alloc() failed");
return CS_FAIL;
}
if (blk_init(blkdesc, CS_BLK_IN,
Ex_tabname, strlen(Ex_tabname)) == CS_FAIL)
{
ex_error("BulkCopyIn: blk_init() failed");
return CS_FAIL;
}
/*
** Bind the variables to the columns and send the rows,
** and then clean up.
*/
...CODE DELETED.....
return CS_SUCCEED;
}
A CS_BLKDESC structure, also called a bulk-descriptor structure, is the control structure for sending and receiving bulk-copy data. It is a hidden structure that contains information about a particular bulk-copy operation.
Before calling blk_alloc, an application must call the Client-Library routines ct_con_alloc and ct_connect to allocate a CS_CONNECTION structure and open the connection.
blk_alloc must be the first routine called in a bulk-copy operation.
Multiple CS_BLKDESC and CS_COMMAND structures can be allocated on a connection, but only one CS_BLKDESC or CS_COMMAND structure can be active at a time. For more information, see blk_init in this chapter.
To deallocate a CS_BLKDESC structure, an application can call blk_drop.
