National Instruments CAN 372139B-01 - Manual (Page 194)

Chapter 6 Automotive Diagnostic Command Set API for C
Automotive Diagnostic Command Set User Manual 6-30 ni.com
ndStatusToString
Purpose
Returns a description for an error code.
Format
void ndStatusToString(
long errorCode,
char message[],
long *len);
Input
errorCode
The status code (return value) of any other diagnostic functions.
Output
message
Returns a descriptive string for the error code.
len
On input, len must contain the message array length. On return, it contains the number
of valid data bytes in the message array.
Description
When the status code returned from an Automotive Diagnostic Command Set function is
nonzero, an error or warning is indicated. This function obtains an error/warning description
for debugging purposes.
The return code is passed into the errorCode parameter. The len parameter indicates the
number of bytes available in the string for the description. The description is truncated to size
len if needed, but a size of 1024 characters is large enough to hold any description. The text
returned in message is null-terminated, so you can use it with ANSI C functions such as
printf . For C or C++ applications, each Automotive Diagnostic Command Set function
returns a status code as a signed 32-bit integer. The following table summarizes the
Automotive Diagnostic Command Set use of this status.