diff --git a/ChangeLog b/ChangeLog index c8b2b0a72..8c6b06845 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,6 +1,8 @@ 2004-04-02 Henning Meier-Geinitz * NEWS: Updated for sane-backends 1.0.14. + * README.linux: Added some hints about setting permissions with + libusb on Linux 2.6. Removed some obsolete paragraphs. 2004-03-29 Henning Meier-Geinitz diff --git a/README.linux b/README.linux index 8bb72f1d5..42423fb9c 100644 --- a/README.linux +++ b/README.linux @@ -1,3 +1,27 @@ +Information about USB scanners: +================================ + +With Linux 2.4.* you could either use the kernel scanner module or libusb to +access USB scanners. In Linux 2.6.4 the kernel scanner module was removed. +Therefore with this and later kernels libusb must be used. + +While SANE automatically uses libusb when the library and its header file were +present during the build of sane-backends, setting permissions will require +some attention. + +The device files used by libusb are located in /proc/bus/usb/ +(e.g. /proc/bus/usb/001/003). The exact file name can be found out by running +sane-find-scanner which would print "libusb:001:003" in this case. While +setting permissions with e.g. "chmod a+rw /proc/bus/usb/001/003" seems to work, +this change is not permanent. The permissions will be reset when the scanner is +replugged or Linux is rebooted. + +One solution to set permissions on-the-fly are the Linux hot-plug tools that +should come with any current distribution. SANE itsself comes with a hotplug +script and related documentaion in the tools/hotplug/ directory. Please refer to +the README in that directory for the details. + + Information about SCSI scanners: ================================ @@ -84,12 +108,6 @@ about missing SCSI headers. Other Information ================= -Compilation errors in /usr/include/linux/videodev.h: These errors happen if - there is a link /usr/include/linux -> /usr/src/linux/include/linux. Most - distributions come with their own Linux-specific headers so this link is - ususally not a good idea (and frowned upon by the kernel hackers). As a - workaround, make sure that the link points to a Linux 2.4 kernel (not 2.6). - Excessive warnings "pointer of type `void *' used in arithmetic": Some older versions of glibc generate these warnings not related to SANE source code. To suppress these warnings do @@ -98,11 +116,6 @@ Excessive warnings "pointer of type `void *' used in arithmetic": and rerun configure. -Older gcc compilers may abort with error "virtual memory exhausted", - usually in canon.c. Try to compile with lower optimization levels: - make CFLAGS="-g -Wall -O1", make CFLAGS="-g -Wall -O", or - make CFLAGS="-g -Wall". - If you use DEC cc on Linux Alpha, you may need to set LDFLAGS="-N" to be able to build sane-backends.