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 fieldInfo()
 Retrieve information about a column
------------------------------------------------------------------------------
 Prototype

     ERRCODE fieldInfo(
                             AREAP  wa,
                             USHORT uiFieldNum,
                             USHORT uiInfoType,
                             ITEM   itmInfo
                          )

 Arguments

     wa is a pointer to self.

     uiFieldNum specifies the ordinal position of the column from which
     information will be retrieved.

          uiInfoType specifies the type of the information to be provided.

     itmInfo is a pointer to a CA-Clipper item which will contain the
     field information.

 Description

     fieldInfo() retrieves information about the column.  The
     information requested is defined by the value passed in uiInfoType.  The
     field information that is available is defined by the RDD.  In the DBF
     work area model, this is limited to the information stored in the DBF
     file structure (that is, name, length, number of decimals, and data
     type).

 Default Behavior

     The fieldInfo() method is used to implement the DBFieldInfo()
     function.  In the default implementation, there are four properties
     (shown in the table below) defined for each column (the numeric
     constants are defined in the header file Rdd.api).

     fieldInfo() Information types
     ------------------------------------------------------------------------
     Constant     Meaning
     ------------------------------------------------------------------------
     DBS_NAME     Obtain the field's name
     DBS_LEN      Obtain the field's length
     DBS_DEC      Obtain the number of decimal places
     DBS_TYPE     Obtain the field's type
     ------------------------------------------------------------------------

     Warning!  itmInfo must be a valid item.

 Implementation Notes

     .  You must implement new behavior for this method only if your
        driver requires properties in addition to those listed in the previous
        table.  Note that the properties listed above are required for every
        implementation.

     .  If your implementation of fieldInfo() cannot determine the
        return value based on the value of uiInfoType, you should allow the
        work area default implementation to attempt it by calling
        SUPER_FIELDINFO().

     .  If itmInfo contains a value other than NIL, it is the new
        value for the property.  If your implementation warrants, you can
        change itmInfo by assigning the new value to it.

     .  The first 1000 possible values for uiInfoType are reserved by
        CA-Clipper.

 Files  Header file is Rdd.api.


See Also: AREA info() orderInfo() recInfo()
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