taglinefilesource code
tx_under714drivers/char/scc.cscc->stat.tx_under++;    /* oops, an underrun! count 'em */
tx_under726drivers/char/scc.cscc->stat.tx_under = 9999;  /* errr... yes. */
tx_under193include/linux/scc.hunsigned int tx_under;  /* Transmitter Underruns */