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owexist(1)

NAME

   owdir,   owread,  owwrite,  owget,  owexist,  owpresent  -  lightweight
   owserver access

SYNOPSIS

   Minimal options
   owdir -s [host:]port [directory]
   owread -s [host:]port filepath
   owwrite -s [host:]port filepath value
   owget -s [host:]port [directory] | filepath

   Server discovery
   owdir --autoserver [directory]
   owread --autoserver filepath
   owwrite --autoserver filepath value
   owget --autoserver [directory] | filepath

   Full options
   owdir -q --quiet -f --format f[.]i[[.]c] ] [  --dir  ]  -s  [host:]port
   [directory] [directory2 ...]

   owread -q --quiet -C --celsius -K --kelvin -F --fahrenheit -R --rankine
   [ --hex ] [ --start= offset ] [ --size= bytes ] -s [host:]port filepath
   [filepath2 ...]

   owwrite  -q  --quiet  -C  --celsius  -K  --kelvin  -F  --fahrenheit  -R
   --rankine [ --hex ] [ --start= offset ] -s [host:]port  filepath  value
   [filepath2 value2 ...]

   owget  -q  --quiet  -f --format f[.]i[[.]c] -C --celsius -K --kelvin -F
   --fahrenheit -R --rankine [ --hex ] [ --start= offset ] [ --size= bytes
   ] [ --dir ] -s [host:]port [directory] | filepath

   Version
   owdir -V --version
   owread -V --version
   owwrite -V --version
   owget -V --version

   Help
   owdir -h | --help
   owread -h | --help
   owwrite -h | --help
   owget -h | --help

DESCRIPTION

   1-Wire
   1-wire  is  a  wiring  protocol  and  series  of  devices  designed and
   manufactured by Dallas Semiconductor, Inc. The bus is a low-power  low-
   speed low-connector scheme where the data line can also provide power.

   Each  device  is  uniquely and unalterably numbered during manufacture.
   There  are  a  wide  variety  of  devices,  including  memory,  sensors
   (humidity,  temperature,  voltage,  contact, current), switches, timers
   and data loggers. More complex devices (like thermocouple sensors)  can
   be  built  with these basic devices. There are also 1-wire devices that
   have encryption included.

   The 1-wire scheme uses a single bus master and multiple slaves  on  the
   same  wire.  The bus master initiates all communication. The slaves can
   be individually discovered and addressed using their unique ID.

   Bus masters come in  a  variety  of  configurations  including  serial,
   parallel, i2c, network or USB adapters.

   OWFS design
   OWFS  is  a  suite of programs that designed to make the 1-wire bus and
   its devices easily accessible. The underlying principle is to create  a
   virtual  filesystem,  with  the  unique ID being the directory, and the
   individual properties of the device are  represented  as  simple  files
   that can be read and written.

   Details  of  the  individual slave or master design are hidden behind a
   consistent interface. The goal is to provide an easy set of tools for a
   software  designer  to create monitoring or control applications. There
   are some performance enhancements in the implementation, including data
   caching,  parallel  access  to  bus  masters, and aggregation of device
   communication. Still  the  fundemental  goal  has  been  ease  of  use,
   flexibility and correctness rather than speed.

   OWSHELL programs
   owdir  owread  owwrite  and  owget  are collectively called the owshell
   programs. They allow lightweight access to an owserver (1) for  use  in
   command line scripts.

   Unlike  owserver  (1)  owhttpd  (1) owftpd (1) owhttpd (1) there is not
   persistent  connection  with  the  1-wire  bus,  no  caching   and   no
   multithreading.  Instead,  each  program connects to a running owserver
   (1) and performs a quick set of queries.

   owserver (1) performs the actual 1-wire connection (to physical  1-wire
   busses  or  other  owserver  programs),  performs  concurrency locking,
   caching, and error collection.

   owshell programs are intended for  use  in  command  line  scripts.  An
   alternative  approach  is  to  mount an owfs (1) filesystem and perform
   direct file lists, reads and writes.

   owdir
   owdir performs a directory listing. With no argument, all  the  devices
   on  the  main  1-wire  bus  will  be listed. Given the name of a 1-wire
   device, the available properties will be listed. It is  the  equivalent
   of

          ls directory

   in the owfs (1) filesystem.

   owread
   owread   obtains   for   value   of  a  1-wire  device  property.  e.g.
   28.0080BE21AA00/temperature gives the DS18B20 temperature.  It  is  the
   equivalent of

          cat filepath

   in the owfs (1) filesystem.

   owwrite
   owwrite  performs  a  change  of  a  property, changing a 1-wire device
   setting or writing to memory. It is the equivalent of

          echo value > filepath

   in the owfs (1) filesystem.

   owget
   owget (1) is a convenience program, combining the function of owdir (1)
   and owread (1) by first trying to read the argument as a directory, and
   if that fails as a 1-wire property.

STANDARD OPTIONS

   --autoserver
   Find an owserver using  the  Service  Discovery  protocol.  Essentially
   Apple's  Bonjour  (aka zeroconf). Only the first owserver will be used,
   and that choice is probably arbitrary.

   -s [host:]port
   Connect via tcp (network) to an owserver process that is connected to a
   physical  1-wire  bus. This allows multiple processes to share the same
   bus. The owserver process can be local or remote.

   If the server option is not specified, the default is the local machine
   and  the  IANA allocated default port of 4304. Thus "-s localhost:4304"
   is the equivalent.

DATA OPTIONS

--hex

   Hexadecimal mode. For reading data, each  byte  of  character  will  be
   displayed  as two characrters 0-9ABCDEF. Most useful for reading memory
   locations. No spaces between data.

   Writing data in hexadecimal mode just means that  the  data  should  be
   given as one long hexadecimal string.

--start=offset

   Read  or write memory locations starting at the offset byte rather than
   the beginning. An offset of 0 means the beginning (and is the default).

--size=bytes

   Read up to the specified number of bytes of a memory location.

HELP OPTIONS

   -h --help
   Shows (this) basic summary of options.

   -V --version
   Version of this program.

DISPLAY OPTIONS

   --dir
   Modify the display of directories to indicate which  entries  are  also
   directories.  A  directory  member  will have a trailing '/' if it is a
   directory itself. This aids recursive searches.

   -f --format f[.]i[[.]c]
   Display format for the  1-wire  devices.  Each  device  has  a  8  byte
   address, consisting of:

   f      family code, 1 byte

   i      ID number, 6 bytes

   c      CRC checksum, 1 byte

   Possible  formats are f.i (default, 01.A1B2C3D4E5F6), fi fic f.ic f.i.c
   and fi.c

   All formats are accepted as input,  but  the  output  will  be  in  the
   specified format.

EXAMPLE

   owdir -s 3000 --format fic
          Get  the  device  listing (full 16 hex digits, no dots) from the
          local owserver at port 3000

   owread -F --autoserver 51.125499A32000/typeK/temperature
          Read temperature from the DS2751-based thermocouple on an  auto-
          discovered owserver Temperature in fahrenheit.

   owwrite -s 10.0.1.2:3001 32.000800AD23110/pages/page.1 "Passed"
          Connect  to  a OWFS server process ( owserver ) that was started
          on another machine at tcp port 3001 and write to the memory of a
          DS2780

AVAILABILITY

   http://www.owfs.org

AUTHOR

   Paul Alfille (paul.alfille@gmail.com)

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