sane-net(5)              SANE Scanner Access Now Easy              sane-net(5)

NAME
       sane-net - SANE network backend

DESCRIPTION
       The sane-net library implements a SANE (Scanner Access Now Easy)
       backend that provides access to image acquisition devices through a
       network connection.  This makes it possible to control devices attached
       to a remote host and also provides a means to grant users access to
       protected resources.


DEVICE NAMES
       This backend expects device names of the form:

              host:device

       Where host is the name (or IP address) of the (remote) host and device
       is the name of the device on this host that should be addressed.  If
       the device name does not contain a colon (:), then the entire string is
       treated as the device string for the default host.  The default host is
       the host listed last in the configuration file (see below).

       An IPv6 address can be specified enclosed in square brackets:

              [::1]:device

CONFIGURATION
       The net.conf file contains both backend options and a list of host
       names (or IP addresses) that should be contacted for scan requests.
       Anything that isn't one of the options listed below will be treated as
       an host name.

       connect_timeout = nsecs
              Timeout (in seconds) for the initial connection to the saned(8)
              server. This will prevent the backend from blocking for several
              minutes trying to connect to an unresponsive saned(8) host
              (network outage, host down, ...). The environment variable
              SANE_NET_TIMEOUT can also be used to specify the timeout at
              runtime.

       Empty lines and lines starting with a hash mark (#) are ignored.  Note
       that IPv6 addresses in this file do not need to be enclosed in square
       brackets.  A sample configuration file is shown below:

              scan-server.somedomain.firm
              192.168.0.1
              # this is a comment
              localhost
              ::1

       The above list of hosts can be extended at run-time using environment
       variable SANE_NET_HOSTS.  This environment variable is a colon-
       separated list of hostnames or IP addresses that should be contacted in
       addition to the hosts mentioned in the configuration file.  For
       example, a user could set the environment variable to the string:

              new.scanner.com:[::1]:192.168.0.2:scanner.univ.edu

       To request that hosts new.scanner.com , [::1] , 192.168.0.2 and
       scanner.univ.edu are contacted in addition to the hosts listed above.

       For this backend to function properly, it is also necessary to define
       the sane-port service in /etc/services using a line of the following
       form:

              sane-port 6566/tcp # SANE network scanner daemon

FILES
       /etc/sane.d/net.conf
              The backend configuration file (see also description of
              SANE_CONFIG_DIR below).

       /usr/lib/sane/libsane-net.a
              The static library implementing this backend.

       /usr/lib/sane/libsane-net.so
              The shared library implementing this backend (present on systems
              that support dynamic loading).

ENVIRONMENT
       SANE_CONFIG_DIR
              This environment variable specifies the list of directories that
              may contain the configuration file.  On *NIX systems, the
              directories are separated by a colon (`:'), under OS/2, they are
              separated by a semi-colon (`;').  If this variable is not set,
              the configuration file is searched in two default directories:
              first, the current working directory (".") and then in
              /etc/sane.d.  If the value of the environment variable ends with
              the directory separator character, then the default directories
              are searched after the explicitly specified directories.  For
              example, setting SANE_CONFIG_DIR to "/tmp/config:" would result
              in directories tmp/config, ., and /etc/sane.d being searched (in
              this order).

       SANE_NET_HOSTS
              A colon-separated list of host names or IP addresses to be
              contacted by this backend.

       SANE_NET_TIMEOUT
              Number of seconds to wait for a response from the saned(8)
              server for the initial connection request.

       SANE_DEBUG_NET
              If the library was compiled with debug support enabled, this
              environment variable controls the debug level for this backend.
              E.g., a value of 128 requests all debug output to be printed.
              Smaller levels reduce verbosity.

BUGS
       If saned(8) has timed out, the net backend may loop with authorization
       requests.


SEE ALSO
       sane(7), saned(8), sane-dll(5), scanimage(1)

       http://www.penguin-breeder.org/?page=sane-net

AUTHOR
       David Mosberger and Andreas Beck

                                  14 Jul 2008                      sane-net(5)