DR_ApDescribePnt

Cogent API and Utilities: Version 4.1
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# `DR_ApDescribePnt`

`DR_ApDescribePnt` -- gives a description of a point.

## Syntax

``int DR_ApDescribePnt`(char * pnt_name, int * pnt_type, int * enabled, int * readable, int * writeable, char * address, int addr_len, char ** error);`

## Arguments

`pnt_name`

  A string containing the name of the required point.

`pnt_type`

  If not `NULL` and the point is defined, then the type of the point is returned here. The following point types are defined (see `dr_api.h`):

          * DR_API_DOUBLE_TYPE
          * DR_API_INT16_TYPE
          * DR_API_BIT_TYPE

`enabled`

  If not `NULL` and the point is defined, then the status of the point is returned here, `1` if enabled, `0` if disabled.

`readable`

  If not `NULL` and the point is defined, then `1` is returned if the point is configured as readable.

`writeable`

  If not `NULL` and the point is defined, then `1` is returned if the point is configured as writeable.

`address`

  If not `NULL`, the address of a string to be set to the point's address string, as specified during the configuration.

`addr_len`

  The maximum length of the address string. Although addressing requirements vary with the type of driver and point, 16 characters is usually sufficient.

`error`

  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:

        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 gets a description of the named point.

## Example

        int         enabled, readable, writeable, type;
        char        *name = "counter";
        char        address[16];
        char        *error_str;

        if result = DR_ApDescribePoint (name, &type, &enabled,
                                        &readable, &writeable,
                                        address, sizeof(address), &error_str))
        {
                printf ("     Error@DescribePoint (%d, %s)\n",
                        result, error_str);
        }
        else
        {
                printf ("     Point %s: type %d, %s%s, addr: %s\n",
                        test_pnt, type, (readable?"R":""),
                        (writeable?"W":""), address);
        }

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