Interpreting input and output parameters in CLI trace files

As is the case with any regular function, DB2® Call Level Interface (CLI) functions have input and output parameters. In a CLI trace, these input and output parameters can be seen, providing details about how each application is invoking a particular CLI API. The input and output parameters for any CLI function, as shown in the CLI trace, can be compared to the definition of that CLI function in the CLI Reference sections of the documentation.

Here is a snippet from a CLI trace file:

SQLConnect( hDbc=0:1, szDSN="sample", cbDSN=-3, szUID="",
            cbUID=-3, szAuthStr="", cbAuthStr=-3 ) 
    ---> Time elapsed - +6.960000E-004 seconds 

SQLRETURN   SQLConnect       (
            SQLHDBC           ConnectionHandle,  /* hdbc */
            SQLCHAR      *FAR ServerName,        /* szDSN */
            SQLSMALLINT       NameLength1,       /* cbDSN */
            SQLCHAR      *FAR UserName,          /* szUID */
            SQLSMALLINT       NameLength2,       /* cbUID */
            SQLCHAR      *FAR Authentication,    /* szAuthStr */
            SQLSMALLINT       NameLength3);      /* cbAuthStr */

The initial call to the CLI function shows the input parameters and the values being assigned to them (as appropriate).

When CLI functions return, they show the resultant output parameters, for example:

SQLAllocStmt( phStmt=1:1 ) 
    <--- SQL_SUCCESS   Time elapsed - +4.444000E-003 seconds 

In this case, the CLI function SQLAllocStmt() is returning an output parameter phStmt with a value of "1:1" (connection handle 1, statement handle 1).