Cogent C API and Utilities : Version 6.4
	Cogent Driver Functions

`DR_ApReadPoint`

DR_ApReadPoint — reads the value of a point.

Syntax

#include <cogent.h>
int DR_ApReadPoint( char*   pnt_name, 
  int*   pnt_type, 
  DR_ApValue_t*   pnt_value, 
  char**   error);

Arguments

pnt_name: A string containing the name of the required point.
pnt_type: A pointer to an integer to return the point type code. This is needed to access the pnt_value. The list of defined driver data point types is described in the Overview section of the Device Driver for Hilscher Fieldbus Cards manual. This parameter can be NULL if the type of point is already known.
pnt_value: A pointer to the memory area to receive the point value. pnt_value is a union of the different types, and pnt_type is used to access the data.
error: The address of a string pointer. In case of error (non-zero return), the string pointer is set to the corresponding error description string. The error string is contained in a static buffer and remains valid only until the next API call. The parameter may be NULL if no error string is required.

Returns

The integer value 0 if the point was accessed successfully, otherwise one of the following error codes is returned:

DR_ERR_PNT_NOT_FOUND
DR_ERR_PNT_NOT_ENABLED
DR_ERR_PNT_NOT_READABLE
DR_ERR_PNT_TYPE_NO_REP
DR_API_STATUS_ERRORS 
DR_API_IPC_ERRORS

Description

This function reads the current value of the named point.

Example

int             type, result;
DR_ApValue_t    value;
char            *error_str, *name = "Pushbutton";

result = DR_ApReadPoint (name, &type, &value, &error_str);
if (result == 0)
{
    printf ("     Pnt: %s ", name);
	switch(type)
	{
      case DR_API_DOUBLE_TYPE:
          printf ("(real) = %f\n", value.d);
          break;
      case DR_API_INT32_TYPE:
          printf ("(int) = %d\n", value.i);
          break;
      case DR_API_INT16_TYPE:
          printf ("(short) = %d\n", value.s);
          break;
      case DR_API_BIT_TYPE:
          printf ("(bit) = %1X\n", value.s);
          break;
      default:
          printf ("(%d) = %X\n", type, value.i);
	}
}
else
      printf ("     Error@ListPoints:%s (%d, %s): \n",
              name, result, error_str);

`int DR_ApReadPoint(`	char*	`pnt_name`,
	int*	`pnt_type`,
	DR_ApValue_t*	`pnt_value`,
	char**	`error)`;


DR_ApReadControl		DR_ApReadStatus