port
where port is the I/O port address at which the device resides. This address is normally specified in hexadecimal using C syntax (e.g., 0x37b) and may be prefixed with the letter "u" (e.g., u0x37b) to force the backend to access the camera in uni-directional mode.
In general, it is safest to list only the port addresses that really correspond to a QuickCam. For example, if one of the listed addresses actually connect to a printer, then starting up this backend will cause the printer to perform a device reset (which is generally undesirable).
@CONFIGDIR@/qcam.conf The backend configuration file (see also description of SANE_CONFIG_DIR below).
@LIBDIR@/libsane-qcam.a The static library implementing this backend.
@LIBDIR@/libsane-qcam.so The shared library implementing this backend (present on systems that support dynamic loading).
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 @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 SANE_CONFIG_DIR to "/tmp/config:" would result in directories tmp/config , . , and @CONFIGDIR@ being searched (in this order).
SANE_DEBUG_QCAM 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.
The program needs root-privileges since it needs to be able to access the camera's I/O ports.