Rockwell Automation 1747-PCINT API Software for 1746 I/O - Manual (Page 74)

6–20 Library of Routines OC_ExtendedErrorMsg
Publication 1747-6.5.3 June 1998
Example:
HANDLE Handle;
OCEXTERR exterr;
char *msg;
int retcode;
/* Should already have called OC_GetExtendedError() to obtain exterr */
retcode = OC_ExtendedErrorMsg( Handle, &exterr, &msg );
printf(“ERROR:%s\n”, msg);