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.  The sane service should be defined 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/x86_64-linux-gnu/sane/libsane-net.a
              The static library implementing this backend.

       /usr/lib/x86_64-linux-gnu/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)