kopia lustrzana https://gitlab.com/sane-project/backends
179 wiersze
4.8 KiB
Groff
179 wiersze
4.8 KiB
Groff
.TH sane\-dll 5 "13 Jul 2008" "@PACKAGEVERSION@" "SANE Scanner Access Now Easy"
|
|
.IX sane\-dll
|
|
.SH NAME
|
|
sane\-dll \- SANE dynamic backend loader
|
|
.SH DESCRIPTION
|
|
The
|
|
.B sane\-dll
|
|
library implements a SANE (Scanner Access Now Easy) backend that
|
|
provides access to an arbitrary number of other SANE backends. These
|
|
backends may either be pre-loaded at the time the
|
|
.B sane\-dll
|
|
library is built or, on systems that support dynamic loading of shared
|
|
libraries, the backends may be loaded at runtime. In the latter case,
|
|
adding support for a new backend simply involves installing the
|
|
relevant library in
|
|
.I @LIBDIR@
|
|
and adding an entry to the
|
|
.I dll.conf
|
|
configuration file. In other words, no applications need to be
|
|
modified or recompiled to add support for new devices.
|
|
.SH "DEVICE NAMES"
|
|
This backend expects device names of the form:
|
|
.PP
|
|
.RS
|
|
.IR backend : device
|
|
.RE
|
|
.PP
|
|
Where
|
|
.I backend
|
|
is the name of the backend and
|
|
.I device
|
|
is the name of the device in this backend that should be addressed.
|
|
If the device name does not contain a colon (:), then the entire string
|
|
is treated as the
|
|
.I device
|
|
string for the default backend. The default backend is the backend
|
|
listed last in the configuration file (see below) or the first
|
|
pre-loaded backend (if any).
|
|
.SH CONFIGURATION
|
|
The contents of the
|
|
.I dll.conf
|
|
file is a list of backend names that may be loaded dynamically upon demand.
|
|
Empty lines are ignored, also everything after a hash mark (#). A sample
|
|
configuration file is shown below:
|
|
.PP
|
|
.RS
|
|
net
|
|
.br
|
|
# this is a comment
|
|
.br
|
|
pnm
|
|
.br
|
|
mustek
|
|
.RE
|
|
.PP
|
|
It is also possible to add a file in
|
|
.I @CONFIGDIR@/dll.d
|
|
that contains the list of backends to be added. Backends mentioned in a
|
|
file included in this directory will be added before any backends listed
|
|
in
|
|
.I dll.conf.
|
|
Files in
|
|
.I @CONFIGDIR@/dll.d
|
|
can be freely named. They shall follow the format conventions as apply for
|
|
.I dll.conf.
|
|
|
|
.PP
|
|
Note that backends that were pre-loaded when building this library do
|
|
not have to be listed in this configuration file. That is, if a
|
|
backend was preloaded, then that backend will always be present,
|
|
regardless of whether it's listed in the configuration file or not.
|
|
.PP
|
|
The list of preloaded backends is determined by macro
|
|
.B PRELOADABLE_BACKENDS
|
|
in file backend/Makefile.in of the SANE source code distribution. After
|
|
changing the value of this macro, it is necessary to reconfigure, rebuild,
|
|
and reinstall SANE for the change to take effect.
|
|
|
|
Aliases are defined in the config file
|
|
.IR dll.aliases .
|
|
It can contain entries of the form
|
|
.PP
|
|
.RS
|
|
.br
|
|
alias SomeName SaneDeviceName
|
|
.br
|
|
alias "Some Name" SaneDeviceName
|
|
.br
|
|
hide SaneDeviceName
|
|
.RE
|
|
.PP
|
|
For example:
|
|
|
|
.PP
|
|
.RS
|
|
.br
|
|
alias Epson net:somehost:epson:/dev/sgX
|
|
.br
|
|
alias "Siemens ST400" st400:/dev/sgY
|
|
.br
|
|
hide net:somehost:pnm:0
|
|
.br
|
|
hide net:somehost:pnm:1
|
|
.br
|
|
alias "Read from file" pnm:0
|
|
.br
|
|
hide pnm:1
|
|
.RE
|
|
.PP
|
|
|
|
Aliased device names are automatically hidden.
|
|
|
|
The idea is that users don't have to deal with complicated device
|
|
names (especially for networked devices), and to hide other exported
|
|
devices which might confuse them. Note that a hidden device can still
|
|
be accessed if the device name is known, it just doesn't appear on the
|
|
list.
|
|
|
|
.SH FILES
|
|
.TP
|
|
.I @CONFIGDIR@/dll.aliases
|
|
The list of aliased or hidden backends.
|
|
.TP
|
|
.I @CONFIGDIR@/dll.conf
|
|
The backend configuration file (see also description of
|
|
.B SANE_CONFIG_DIR
|
|
below).
|
|
.TP
|
|
.I @LIBDIR@/libsane\-dll.a
|
|
The static library implementing this backend.
|
|
.TP
|
|
.I @LIBDIR@/libsane\-dll.so
|
|
The shared library implementing this backend (present on systems that
|
|
support dynamic loading).
|
|
.SH ENVIRONMENT
|
|
.TP
|
|
.B SANE_CONFIG_DIR
|
|
This environment variable specifies the list of directories that may
|
|
contain the configuration file. Under UNIX, 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 @CONFIGDIR@. 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
|
|
.B SANE_CONFIG_DIR
|
|
to "/tmp/config:" would result in directories "tmp/config", ".", and
|
|
"@CONFIGDIR@" being searched (in this order).
|
|
.TP
|
|
.B SANE_DEBUG_DLL
|
|
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.
|
|
|
|
.ft CR
|
|
.nf
|
|
Value Description
|
|
0 print severe errors only
|
|
1 print normal errors and important messages
|
|
2 print normal messages
|
|
3 print debugging messages
|
|
4 print everything
|
|
.fi
|
|
.ft R
|
|
|
|
Example:
|
|
export SANE_DEBUG_DLL=3
|
|
|
|
|
|
.SH "SEE ALSO"
|
|
.BR sane (7),
|
|
.BR scanimage (1),
|
|
.BR sane\-"backendname" (5)
|
|
|
|
.SH AUTHOR
|
|
David Mosberger
|