int offset = 0;
va_start(argp, logstring);
offset = sprintf(buf, "DEBUG: ");
vsnprintf(&buf[offset], STRSIZE - offset, logstring, argp);
va_end(argp);
int offset = 0;
va_start(argp, logstring);
offset = sprintf(buf, "DEBUG: ");
vsnprintf(&buf[offset], STRSIZE - offset, logstring, argp);
va_end(argp);