An integer expression indicating the order of the parameter. Use 1 for the first parameter, 2 for the second parameter, and so on.
data-type
A character expression indicating the data type of the parameter and evaluating to one of the following:
"CHARACTER"
"DATASET-HANDLE"
"DATE"
"DATETIME"
"DATETIME-TZ"
"DECIMAL"
"HANDLE"
"INT64"
"INTEGER"
"LOGICAL"
"LONGCHAR"
"MEMPTR"
"RAW"
"ROWID"
"TABLE-HANDLE"
TABLE-HANDLE can be a handle to a static or dynamic temp-table. Likewise, DATASET-HANDLE can be a handle to a static or dynamic ProDataSet object.
Note: To manage BUFFER parameters, use HANDLE parameters.
For each parameter, the data type specified by the caller and the callee must be compatible. For example, an ABL application must specify a 64-bit ABL data type (INT64) when calling a DLL routine that expects a 64-bit signed integer. The ABL program cannot declare the ABL variable as LONG or UNSIGNED-LONG and expect the correct behavior. Similarly, if a DLL routine expects a 32-bit value, the ABL program must specify a 32-bit ABL data type (LONG or UNSIGNED-LONG). The ABL program cannot declare the ABL variable as a SHORT or UNSIGNED-SHORT and expect the correct behavior.
When invoking a Windows DLL or UNIX shared library function, ABL DLL data types are valid as data-type values. data-type specifies the type expected by the DLL or shared library routine parameter. For example, the parameter data-type is set to "LONG" if the DLL routine parameter expects "LONG". For a list of valid ABL DLL data types, see the DEFINE PARAMETER statement.
If a DLL data type is specified for a non-DLL invocation, the AVM raises a run-time error.
Note: If you pass an ABL character string to a UNIX shared library routine, you can pass it as a CHARACTER variable or expression. However, if you expect the shared library routine to modify the value, Progress Software Corporation recommends that you pass a MEMPTR containing a null-terminated character string.
iomode
A character expression indicating the mode of the parameter and evaluating to one of the following:
"INPUT"
"OUTPUT"
"INPUT-OUTPUT"
"OUTPUT-APPEND"
For each parameter, the mode specified by the caller and the callee must match.
For parameters of attributes, specify "INPUT".
For TABLE-HANDLE output parameters whose output is to be appended to the table, and in no other case, specify "OUTPUT-APPEND".
If data-type is "DATASET-HANDLE" or "TABLE-HANDLE", you can append "-by-reference" to any previously listed iomode.
parameter-value
An expression whose type is compatible with data-type.
The parameter-value argument may represent a determinate or indeterminate array. However, you cannot pass an array by value. You can pass an array only as a variable defined using the DEFINE VARIABLE statement with the EXTENT option. If you include the EXTENT keyword in the data-type argument, the AVM ignores it. If you include the array element values in the parameter-value argument, ABL generates a compile error.
If iomode is "INPUT" or "INPUT-OUTPUT", if the data type of parameter-value does not agree with the data type passed, parameter-value will automatically be converted to the data type passed during SET-PARAMETER( ) processing.
If iomode is "OUTPUT" or "INPUT-OUTPUT", each of the following must be true:
parameter-value must represent a program variable or a NO-UNDO TEMP-TABLE field (perhaps with an array reference).
parameter-value must still be in scope and must still be valid when the dynamic invoke is executed.
If the output value from the called procedure does not have a data type that matches the data type passed, the output value will be converted to the data type passed.
If iomode is "OUTPUT", parameter-value is ignored if the ASYNCHRONOUS attribute is TRUE.
A procedure or user-defined function you want to invoke dynamically