Observação:Estou ciente de que esta pergunta parece ser uma duplicata de"E: Pacote '' não tem candidato para instalação", mas a única resposta postada nessa pergunta não me ajudou em nada. Tentei incluir mais informações do que naquela pergunta, incluindo os resultados de todas as sugestões nos comentários e nas respostas.
Fundo:Eu tenho um Raspberry Pi 1 Modelo B, rodando o Raspbian Wheezy, no qual já instalei o ROS (o sistema operacional do robô), mas com o qual não fiz muito mais. Esta semana, tenho tentado instalar alguns pacotes ROS extras do código-fonte. Ao tentar corrigir vários problemas de compilador e dependência (admito que estava me debatendo ao executar comandos aleatórios da Internet - os problemas começaram depois que tentei atualizar o libboost e, em seguida, tentei revertê-lo para a versão anterior), eu aparentemente conseguiu mangueirar completamente o apt-getsistema.
Meu problema é que apt-getnão consigo mais instalar nada com sucesso. Tudo o que tentei termina com um erro "E: O pacote 'nome do pacote' não tem candidato para instalação" (sim, executei sudo apt-get updaterepetidamente, comdiversas variações em sources.list). Tudo também está atualizado, de acordo com apt-get upgradee apt-get dist-upgrade. aptitudenão se sai melhor em instalar coisas.
Gostaria de consertar a instalação existente, mas estou disposto a reiniciar a partir de uma nova imagem se o sistema não puder ser recuperado sem um trabalho extenso - fiz backup de tudo que é importante.
Aqui está o conteúdo de todos os arquivos .list no diretório /etc/apt/:
pi@raspberrypi ~ $ find /etc/apt/ -path *.list | xargs tail -n +1
==> /etc/apt/sources.list.d/collabora.list <==
deb http://raspberrypi.collabora.com wheezy rpi
==> /etc/apt/sources.list.d/ros-latest.list <==
deb http://packages.ros.org/ros/ubuntu wheezy main
==> /etc/apt/sources.list.d/raspi.list <==
deb http://archive.raspberrypi.org/debian/ wheezy main
# Uncomment line below then 'apt-get update' to enable 'apt-get source'
#deb-src http://archive.raspberrypi.org/debian/ wheezy main
==> /etc/apt/sources.list <==
deb http://mirrordirector.raspbian.org/raspbian/ wheezy main contrib non-free rpi
# Uncomment line below then 'apt-get update' to enable 'apt-get source'
#deb-src http://archive.raspbian.org/raspbian/ wheezy main contrib non-free rpi
deb-src http://mirrordirector.raspbian.org/raspbian/ testing main contrib non-free rpi
#deb http://raspbian.mirrors.lucidnetworks.net/raspbian/ wheezy main contrib non-free rpi
#deb http://archive.raspbian.org/raspbian wheezy main contrib non-free rpi
# Source repository to add
#deb-src http://archive.raspbian.org/raspbian wheezy main contrib non-free rpi
#deb http://mirrordirector.raspbian.org/raspbian/ jessie main contrib non-free rpi
#deb http://archive.raspbian.org/raspbian jessie main contrib non-free rpi
# Source repository to add
#deb-src http://archive.raspbian.org/raspbian jessie main contrib non-free rpi
Aqui está a saída de apt-get update, apt-get upgradee apt-get upgrade:
pi@raspberrypi ~ $ sudo apt-get update
Hit http://packages.ros.org wheezy Release.gpg
Hit http://raspberrypi.collabora.com wheezy Release.gpg
Hit http://archive.raspberrypi.org wheezy Release.gpg
Hit http://packages.ros.org wheezy Release
Hit http://raspberrypi.collabora.com wheezy Release
Hit http://archive.raspberrypi.org wheezy Release
Hit http://mirrordirector.raspbian.org wheezy Release.gpg
Hit http://mirrordirector.raspbian.org testing Release.gpg
Hit http://packages.ros.org wheezy/main armhf Packages
Hit http://mirrordirector.raspbian.org wheezy Release
Hit http://raspberrypi.collabora.com wheezy/rpi armhf Packages
Hit http://mirrordirector.raspbian.org testing Release
Hit http://archive.raspberrypi.org wheezy/main armhf Packages
Hit http://mirrordirector.raspbian.org wheezy/main armhf Packages
Hit http://mirrordirector.raspbian.org wheezy/contrib armhf Packages
Hit http://mirrordirector.raspbian.org wheezy/non-free armhf Packages
Ign http://packages.ros.org wheezy/main Translation-en_GB
Ign http://packages.ros.org wheezy/main Translation-en
Hit http://mirrordirector.raspbian.org wheezy/rpi armhf Packages
Ign http://raspberrypi.collabora.com wheezy/rpi Translation-en_GB
Ign http://archive.raspberrypi.org wheezy/main Translation-en_GB
Ign http://raspberrypi.collabora.com wheezy/rpi Translation-en
Ign http://archive.raspberrypi.org wheezy/main Translation-en
Hit http://mirrordirector.raspbian.org testing/main Sources
Hit http://mirrordirector.raspbian.org testing/contrib Sources
Hit http://mirrordirector.raspbian.org testing/non-free Sources
Hit http://mirrordirector.raspbian.org testing/rpi Sources
Ign http://mirrordirector.raspbian.org wheezy/contrib Translation-en_GB
Ign http://mirrordirector.raspbian.org wheezy/contrib Translation-en
Ign http://mirrordirector.raspbian.org wheezy/main Translation-en_GB
Ign http://mirrordirector.raspbian.org wheezy/main Translation-en
Ign http://mirrordirector.raspbian.org wheezy/non-free Translation-en_GB
Ign http://mirrordirector.raspbian.org wheezy/non-free Translation-en
Ign http://mirrordirector.raspbian.org wheezy/rpi Translation-en_GB
Ign http://mirrordirector.raspbian.org wheezy/rpi Translation-en
Reading package lists... Done
pi@raspberrypi ~ $ sudo apt-get upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
pi@raspberrypi ~ $ sudo apt-get dist-upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Aqui está o que acontece quando tento instalar um programa simples e agradável, bc:
pi@raspberrypi ~ $ sudo apt-get install bc
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package bc is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
E: Package 'bc' has no installation candidate
Finalmente, aqui estão alguns resultados do apt-cache que podem ser relevantes. Eu tenho todas as dependências instaladas, embora não tenha certeza se é normal que o número da versão do install-info (mínimo necessário?) seja "(nulo)".
pi@raspberrypi ~ $ dpkg --print-architecture
armhf
pi@raspberrypi ~ $ apt-cache dump | grep -m 1 -A 9 'Package: bc$'
Package: bc
Version: 1.06.95-2
File: /var/lib/apt/lists/mirrordirector.raspbian.org_raspbian_dists_wheezy_main_binary-armhf_Packages
Depends: libc6 2.4
Depends: libreadline6 6.0
Depends: dpkg 1.15.4
Depends: install-info (null)
Description Language:
File: /var/lib/apt/lists/mirrordirector.raspbian.org_raspbian_dists_wheezy_main_binary-armhf_Packages
MD5: 5d0bd9bd305e8d8ca79ea90107c2ec5a
pi@raspberrypi ~ $ apt-cache policy bc
bc:
Installed: (none)
Candidate: (none)
Version table:
1.06.95-2 0
-10 http://mirrordirector.raspbian.org/raspbian/ wheezy/main armhf Packages
pi@raspberrypi ~ $ apt-cache policy
Package files:
100 /var/lib/dpkg/status
release a=now
500 http://packages.ros.org/ros/ubuntu/ wheezy/main armhf Packages
release o=ROS,a=wheezy,n=wheezy,l=ROS wheezy,c=main
origin packages.ros.org
500 http://archive.raspberrypi.org/debian/ wheezy/main armhf Packages
release o=Raspberry Pi Foundation,a=oldstable,n=wheezy,l=Raspberry Pi Foundation,c=main
origin archive.raspberrypi.org
500 http://raspberrypi.collabora.com/ wheezy/rpi armhf Packages
release o=Collabora,n=wheezy,l=Collabora Raspberry Pi graphics enablement,c=rpi
origin raspberrypi.collabora.com
-10 http://mirrordirector.raspbian.org/raspbian/ wheezy/rpi armhf Packages
release v=7.0,o=Raspbian,a=oldstable,n=wheezy,l=Raspbian,c=rpi
origin mirrordirector.raspbian.org
-10 http://mirrordirector.raspbian.org/raspbian/ wheezy/non-free armhf Packages
release v=7.0,o=Raspbian,a=oldstable,n=wheezy,l=Raspbian,c=non-free
origin mirrordirector.raspbian.org
-10 http://mirrordirector.raspbian.org/raspbian/ wheezy/contrib armhf Packages
release v=7.0,o=Raspbian,a=oldstable,n=wheezy,l=Raspbian,c=contrib
origin mirrordirector.raspbian.org
-10 http://mirrordirector.raspbian.org/raspbian/ wheezy/main armhf Packages
release v=7.0,o=Raspbian,a=oldstable,n=wheezy,l=Raspbian,c=main
origin mirrordirector.raspbian.org
Pinned packages:
pi@raspberrypi ~ $ apt-cache showpkg bc
Package: bc
Versions:
1.06.95-2 (/var/lib/apt/lists/mirrordirector.raspbian.org_raspbian_dists_wheezy_main_binary-armhf_Packages)
Description Language:
File: /var/lib/apt/lists/mirrordirector.raspbian.org_raspbian_dists_wheezy_main_binary-armhf_Packages
MD5: 5d0bd9bd305e8d8ca79ea90107c2ec5a
Reverse Depends:
simbamond,bc
videogen,bc
shorewall-lite,bc
shorewall-core,bc
shorewall,bc
secvpn,bc
lsb-core,bc
linux-source-3.18,bc
linux-source-3.12,bc
linux-source-3.10,bc
junior-math,bc
ibid,bc
fish,bc
education-common,bc
debian-cd,bc
cups,bc
calamaris,bc
apt-move,bc
Dependencies:
1.06.95-2 - libc6 (2 2.4) libreadline6 (2 6.0) dpkg (18 1.15.4) install-info (0 (null))
Provides:
1.06.95-2 -
Reverse Provides:
pi@raspberrypi ~ $ apt-cache madison bc
bc | 1.06.95-2 | http://mirrordirector.raspbian.org/raspbian/ wheezy/main armhf Packages
bc | 1.06.95-9 | http://mirrordirector.raspbian.org/raspbian/ testing/main Sources
Não estou ficando sem espaço em disco:
pi@raspberrypi ~ $ df -h
Filesystem Size Used Avail Use% Mounted on
/dev/root 59G 6.1G 50G 11% /
devtmpfs 214M 0 214M 0% /dev
tmpfs 44M 252K 44M 1% /run
tmpfs 5.0M 0 5.0M 0% /run/lock
tmpfs 87M 0 87M 0% /run/shm
/dev/mmcblk0p1 56M 20M 36M 36% /boot
EDITAR: Em resposta ao comentário de Gilles, aqui está o meu /etc/apt/preferences:
pi@raspberrypi ~ $ ls /etc/apt/preferences.d
pi@raspberrypi ~ $ cat /etc/apt/preferences
Package: *
Pin: release n=wheezy
Pin-Priority: 900
Package: *
Pin: release n=jessie
Pin-Priority: 300
Package: *
Pin: release o=Raspbian
Pin-Priority: -10