ecu/models/nbssetclk.ep

#  CHK=0x1C17
#+---------------------------------------------------------------
# nbssetclk - use NBSsetclk to set system time
#
# Place this directory entry in your /.ecu/phone file
# and edit as necessary:
#
#  .--[ entry: nbssetclk ]---------------------------------.
#  |                                                       |
#  | telephone number  1(202)653-0351                      |
#  | device            Any                                 |
#  | bit rate          1200                                |
#  | parity            N                                   |
#  | description       Naval Observatory Time              |
#  | debug level       0  (dialer -x value 0-9)            |
#  | DCD watch         n                                   |
#  | RTS/CTS flow ctl  n  (0=off,7=best,n=no change)       |
#  |                                                       |
#  | Enter telephone number                                |
#  | ESC: exit  END: accept  ^U: erase ^B: back  TAB: fwd  |
#  `-------------------------------------------------------'
#
# Run some command like this out of root crontab:
# 30 3 * * 5 /usr/local/bin/ecu -p nbssetclk -D
# which directs this script to run on Friday mornings at 3AM.
# (If you use this, PLEASE CHOOSE A TIME TO CALL OTHER
# THAN SHOWN IN THE EXAMPLE; I'd hate to be responsible for
# a big spike in usage at some given minute. :> )
#
# The script makes $i_retries attempts to connect to NBS DC,
# waiting $i_wait secs between each retry. Upon successful
# connection,
#
# 1. NBSsetclk is invoked to get the time from NBS and set
#    the clock.
#
# 2. If tts can be found at the path in $s_tts, then my
#    TTS ("Tucker Time System") protocol hack broadcasts the
#    new time of day to all listeners on the attached subnet.
#
# 3. If usemorse can be found at the path in $s_morse,
#    my morse driver announces successful time capture.
#
#----------------------------------------------------------------
#+:EDITS:
#:01-24-1997-02:37-wht@yuriatin-SOURCE RELEASE 4.00
#:09-15-1996-06:04-wht@n4hgf-clean up for 4.00
#:09-13-1992-01:26-wht@n4hgf-creation

    # early reinforcement for interactive users
    echo 'Call NBS: ecu pid is '+%itos(%pid)

    # configuration
    $i_retries=10                         # allow this many retries
    $i_wait=7                             # seconds between retries
    $s_tts = '/etc/tts'                   # path to tts
    $s_morse = '/usr/local/bin/usemorse'  # path to usemorse

    # make several attempts to connect
    $i_try = 1                  # first attempt
    $i0 = 1                     # make loop below run 1st time
    whilei $i0 != 0
    {
        echo '--> Dialing attempt '+%itos($i_try)
        dial 'nbssetclk'        # make the call

        # be nice to an interactive user (allow loop abort)
        ifi $i0 == 2            # dial result of 2 says keyboard interrupt
            echo 'SIGINT: calling aborted'; goto SORRY

        # if the call fails otherwise, maybe retry
        ifi $i0 != 0
        {
            $i_try=$i_try+1
            ifi $i_try > $i_retries
                echo '--> Retries exhausted'; goto SORRY
            echo '--> Waiting '+%itos($i_wait)+' seconds ... '
            nap -m $i_wait*1000
            echo '\n'
        }
        # dial returned $i0==0, indicating success
    }

    echo '--> Connected to NBS'

    # update the time of day and the CMOS RAM from NBS-supplied time
    # (NBSsetclk -f switch gets the UNIX file descriptor of our NBS line,
    # reads the time from NBS and sets the clock with stime())
    $s10 = '/etc/NBSsetclk -f '+%itos(%conn)
    gosub EXEC_S10             # execute the command with sexy verbosity
    hangup                     # hangup immediately to save $$$

    # my time protocol hack has a special "one-time master" option
    # to spray the time of day all over the local subnet
    ifnz %isreg($s_tts)        # if the program exists
    {
        $s10 = $s_tts+' -o -m -vvv'
        gosub EXEC_S10
    }

    # my morse driver announces success to anyone in the shack
    ifnz %isreg($s_morse)   # if the program exists
    {
        $s10 = $s_morse+' -f 880 -t 5 nbs'  # 880Hz, .05 sec/baud
        gosub EXEC_S10
    }

    echo '--> SUCCESS!'
    return  # job well done ..............................

# error bailout
SORRY
    echo 'Sorry ... time capture failed '
    return 1 # non-zero return terminates any chain of proc executions

#---------------------------------------------------------------------

# subroutine to execute a shell command with verbosity
EXEC_S10
    echo '--> '+$s10
    system -s $s10
    echo ''
    return # from subroutine