krb5_vprepend_error_message - Add a prefix to the message for an error code using a va_list.

void krb5_vprepend_error_message(krb5_context ctx, krb5_error_code code, const char * fmt, va_list args)

param:

[in] ctx - Library context

[in] code - Error code

[in] fmt - Format string for error message prefix

[in] args - List of vprintf(3) style arguments

This function is similar to krb5_prepend_error_message(), but uses a va_list instead of variadic arguments.