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       libieee1284 - IEEE1284 communications library


               #include <ieee1284.h>
               cc files... -lieee1284


       The libieee1284 library is a library for accessing parallel port

       The model presented to the user is fairly abstract: a list of parallel
       ports with arbitrary names, with functions to access them in various
       ways ranging from bit operations to block data transfer in one of the
       IEEE 1284 sanctioned protocols.

       Although the library resides in user space the speed penalty may not be
       as bad as you initially think, since the operating system may well
       provide assistance with block data transfer operations; in fact, the
       operating system may even use hardware assistance to get the job done.
       So, using libieee1284, ECP transfers using DMA are possible.

       The normal sequence of events will be that the application
        1.  calls ieee1284_find_ports to get a list of available ports
        2.  then ieee1284_get_deviceid to look for a device on each port that
           it is interested in
        3.  and then ieee1284_open to open each port it finds a device it can
           control on.
        4.  The list of ports returned from ieee1284_find_ports can now be
           disposed of using ieee1284_free_ports.
        5.  Then when it wants to control the device, it will call
           ieee1284_claim to prevent other drivers from using the port
        6.  then perhaps do some data transfers
        7.  and then ieee1284_release when it is finished that that particular
           command. This claim-control-release sequence will be repeated each
           time it wants to tell the device to do something.
        8.  Finally when the application is finished with the device it will
           call ieee1284_close.

       Usually a port needs to be claimed before it can be used. This is to
       prevent multiple drivers from trampling on each other if they both want
       to use the same port. The exception to this rule is the collection of
       IEEE 1284 Device IDs, which has an implicit open-claim-release-close
       sequence. The reason for this is that it may be possible to collect a
       Device ID from the operating system, without bothering the device with


       When ieee1284_find_ports is first called, the library will look for a
       configuration file, /etc/ieee1284.conf.

       Comments begin with a ’#’ character and extend to the end of the line.
       Everything else is freely-formatted tokens. A non-quoted (or
       double-quoted) backslash character ’\’ preserves the literal value of
       the next character, and single and double quotes may be used for
       preserving white-space. Braces and equals signs are recognised as
       tokens, unless quoted or escaped.

       The only configuration instruction that is currently recognised is
       “disallow method ppdev”, for preventing the use of the Linux ppdev


       You can enable debugging output from the library by setting the
       environment variable LIBIEEE1284_DEBUG to any value.


           Configuration file.


       parport(3), parport_list(3), ieee1284_find_ports(3),
       ieee1284_free_ports(3), ieee1284_get_deviceid(3), ieee1284_open(3),
       ieee1284_close(3), ieee1284_claim(3), ieee1284_release(3),
       ieee1284_data(3), ieee1284_status(3), ieee1284_control(3),
       ieee1284_negotiation(3), ieee1284_ecp_fwd_to_rev(3),
       ieee1284_transfer(3), ieee1284_get_irq_fd(3), ieee1284_set_timeout(3)


       Tim Waugh <>


       Copyright © 2001-2003 Tim Waugh