---
name: "sane-net"
section: "5"
platform: "linux"
package: "sane"
version: "1.4.0-4"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/sane-net"
---

# sane-net(5)

SANE network backend

## 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)](/saned/8.md) server. This will prevent the backend from blocking for several minutes trying to connect to an unresponsive [**saned**(8)](/saned/8.md) 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)](/saned/8.md) 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)](/saned/8.md) has timed out, the net backend may loop with authorization requests.

## SEE ALSO

[**sane**(7)](/sane/7.md), [**saned**(8)](/saned/8.md), [**sane-dll**(5)](/sane-dll/5.md), [**scanimage**(1)](/scanimage/1.md)

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

## AUTHOR

David Mosberger and Andreas Beck