UVC(http://linux-uvc.berlios.de/) is framework to allow linux work with any webcameras.
Current desktop kernel is compiled without its support.

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ghost ghost # LC_ALL=C ACCEPT_KEYWORDS="~amd64" emerge linux-uvc luvcview

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Calculating dependencies... done!

Verifying ebuild manifests

Starting parallel fetch

Emerging (1 of 2) media-video/linux-uvc-0.1.0_pre250

* linux-uvc-0.1.0_pre250.tar.bz2 RMD160 SHA1 SHA256 size ;-) ... [ ok ] * checking ebuild checksums ;-) ... [ ok ] * checking auxfile checksums ;-) ... [ ok ] * checking miscfile checksums ;-) ... [ ok ] * CPV: media-video/linux-uvc-0.1.0_pre250 * REPO: gentoo * USE: amd64 elibc_glibc kernel_linux multilib userland_GNU * Determining the location of the kernel source code * Found kernel source directory: * /usr/src/linux * Found kernel object directory: * /lib/modules/2.6.31-gentoo-r6/build * Found sources for kernel version: * 2.6.31-gentoo-r6 * Checking for suitable kernel configuration options... * CONFIG_VIDEO_DEV: is not set when it should be. * Please check to make sure these options are set correctly. * Failure to do so may cause unexpected problems. * Once you have satisfied these options, please try merging * this package again. * ERROR: media-video/linux-uvc-0.1.0_pre250 failed: * Incorrect kernel configuration options * * Call stack: * ebuild.sh, line 54: Called pkg_setup * linux-uvc-0.1.0_pre250.ebuild, line 24: Called linux-mod_pkg_setup * linux-mod.eclass, line 585: Called linux-info_pkg_setup * linux-info.eclass, line 888: Called check_extra_config * linux-info.eclass, line 782: Called die * The specific snippet of code: * die "Incorrect kernel configuration options" * * If you need support, post the output of 'emerge --info =media-video/linux-uvc-0.1.0_pre250', * the complete build log and the output of 'emerge -pqv =media-video/linux-uvc-0.1.0_pre250'. * The complete build log is located at '/var/calculate/tmp/portage/media-video/linux-uvc-0.1.0_pre250/temp/build.log'. * The ebuild environment file is located at '/var/calculate/tmp/portage/media-video/linux-uvc-0.1.0_pre250/temp/die.env'. * S: '/var/calculate/tmp/portage/media-video/linux-uvc-0.1.0_pre250/work/linux-uvc-0.1.0_pre250'

Failed to emerge media-video/linux-uvc-0.1.0_pre250, Log file:

'/var/calculate/tmp/portage/media-video/linux-uvc-0.1.0_pre250/temp/build.log'

• Messages for package media-video/linux-uvc-0.1.0_pre250:

• CONFIG_VIDEO_DEV: is not set when it should be.
• Please check to make sure these options are set correctly.
• Failure to do so may cause unexpected problems.
• Once you have satisfied these options, please try merging
• this package again.
• ERROR: media-video/linux-uvc-0.1.0_pre250 failed:
• Incorrect kernel configuration options *
• Call stack:
• ebuild.sh, line 54: Called pkg_setup
• linux-uvc-0.1.0_pre250.ebuild, line 24: Called linux-mod_pkg_setup
• linux-mod.eclass, line 585: Called linux-info_pkg_setup
• linux-info.eclass, line 888: Called check_extra_config
• linux-info.eclass, line 782: Called die
• The specific snippet of code:
• die "Incorrect kernel configuration options" *
• If you need support, post the output of 'emerge --info =media-video/linux-uvc-0.1.0_pre250',
• the complete build log and the output of 'emerge -pqv =media-video/linux-uvc-0.1.0_pre250'.
• The complete build log is located at '/var/calculate/tmp/portage/media-video/linux-uvc-0.1.0_pre250/temp/build.log'.
• The ebuild environment file is located at '/var/calculate/tmp/portage/media-video/linux-uvc-0.1.0_pre250/temp/die.env'.
• S: '/var/calculate/tmp/portage/media-video/linux-uvc-0.1.0_pre250/work/linux-uvc-0.1.0_pre250'