DR_ApDescribePnt
DR_ApDescribePnt — gives a description of a point.
Syntax
#include <cogent.h>
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);
}
