dpkg: unrecoverable fatal error, aborting: reading files list for package 'libxml2:i386': Input/output error E: Sub-process /usr/bin/dpkg returned an error code (2)
I have bumped into an issue that doesn't allow me to do anything related to apt-get: install, remove, etc. Whenever I try to do something (e.g. sudo apt-get install firefox -f) it gives me the same error message:  Reading database ... dpkg: unrecoverable fatal error, aborting:  unable to open files list file for package `fontconfig-config': Input/output error E: Sub-process /usr/bin/dpkg returned an error code (2)   I have tried to deal with the package fontconfig-config without success.  I have found that the "Input/output error" is usually linked with physical problems of the hard drive, but I do not think that's the case I am using that hd without any other problem.  I have tried removing the mention to the package in /var/lib/dpkg/status as mentioned .  I have tried deleting all files related to the package in /var/lib/dpkg/info as I found somewhere.  But I still cannot do anything. The funny bit comes when I look for the file that is giving me troubles:   mecho@Ansible-MS-7680:/var/lib/dpkg/info$ ls fontconfig* ls: cannot access fontconfig-config.list: Input/output error fontconfig.list     fontconfig.postinst  fontconfig.preinst  fontconfig.triggers fontconfig.md5sums  fontconfig.postrm    fontconfig.prerm   This is done after I deleted all files ... it looks like fontconfig-config.list still exists but it doesn't show up!  Any idea about how to solve the problem?  I am on kubuntu precise, fontconfig-config_2.8.0-3ubuntu9.1    I do not have smartmontools installed nor any other programme I could use to check the hard disk. The most similar think I seem to have is KDE Partition Manager but it doesn't allow me to check anything (the option appears unavailable). However, I think the problem is not the hd.  How do you suggests me to do the fs check? fcheck is not installed and I cannot think of any other command in bash (as I do not think I have anything else installed that could perform a check).  Thank you.  Edit: I have found the command (silly me), fsck. This is what I got:  /dev/sda1: recovering journal Clearing orphaned inode 4456702 (uid=1000, gid=1000, mode=0140775, size=0) Clearing orphaned inode 4456700 (uid=1000, gid=1000, mode=0140775, size=0) Clearing orphaned inode 4456699 (uid=1000, gid=1000, mode=0140775, size=0) Clearing orphaned inode 4456697 (uid=1000, gid=1000, mode=0140775, size=0) Clearing orphaned inode 4456694 (uid=1000, gid=1000, mode=0140775, size=0) Clearing orphaned inode 4456693 (uid=1000, gid=1000, mode=0140775, size=0) Clearing orphaned inode 4456688 (uid=1000, gid=1000, mode=0140775, size=0) Clearing orphaned inode 4456481 (uid=1000, gid=1000, mode=0140775, size=0) Clearing orphaned inode 4456692 (uid=0, gid=0, mode=0100600, size=65536) Clearing orphaned inode 4456689 (uid=1000, gid=1000, mode=0140775, size=0) Clearing orphaned inode 4456709 (uid=1000, gid=1000, mode=0100600, size=714046) Clearing orphaned inode 4456469 (uid=1000, gid=1000, mode=0140775, size=0) Clearing orphaned inode 3672644 (uid=0, gid=0, mode=0100644, size=1595) Clearing orphaned inode 1324021 (uid=0, gid=0, mode=0100640, size=1980) Clearing orphaned inode 1324014 (uid=0, gid=0, mode=0100640, size=126) Clearing orphaned inode 4456499 (uid=1000, gid=1000, mode=0100600, size=0) Clearing orphaned inode 4456483 (uid=1000, gid=1000, mode=0100600, size=65536) Setting free inodes count to 7147142 (was 7147702) Setting free blocks count to 23891195 (was 23781617) /dev/sda1: clean, 151930/7299072 files, 5292549/29183744 blocks
I've taken up self-study of math. (How smart can that be?) I've just about finished a course in real analysis which spent a lot of time on metric spaces and some time revisiting calculus.  I was thinking of trying abstract algebra. I would appreciate any book recommendations.  Thanks in advance.  Andrew I have a Canon 550D which I've been using for around a year now. I really love it and have learned a great deal with this and the 18 - 135mm kit lens. But now with experience I feel the need to get some better glass. I won't be buying a new body any time soon because I figure investing in some good glass is more important.   As I have looked around, I see quite a few good used L lenses I can get in ebay for good bargain prices. But I know that the EF lenses don't have the same focal length in the cropped sensors. Is it a wise decision to buy these EF lenses or buy the cropped sensor alternatives?  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Prove that for any $x_0 \in X$ and any $r&gt;0$, the open ball $B_r(x_o)$ is open.   My attempt: Let $y\in B_r(x_0)$. By definition, $d(y,x_0)&lt;r$. I want to show there exists an $r_1\in\mathbb{R^+}$ s.t. $B_{r_{1}}(y)\subseteq B_r(x_0)$. Let $a\in B_{r_{1}}(y)$. Then, $d(a,y)&lt;r_1$. For $a\in B_{r}(x_0)$, $d(a,x_0)&lt;r$. I want to show $d(a,y)&lt;r_1$ implies $d(a,x_0)&lt;r$. By triangle inequality, $d(a,y)\leq d(a,x_0) + d(y,x_0) \rightarrow$  $d(a,y)&lt;r_1\leq d(a,x_0)+d(y,x_0)&lt;2r...$  I'm a little stuck after this point. Copying data over with rsync causes size discrepancies What's the difference between the snap folder in /home/UserName and the snap folder in root (/)? Combining the entries of two lists Since the last update (v1.0.85), I am getting all the question pages blank on the Android app. For those who are confused with the image, I'm using RtL (Right-to-Left) layout.        If I scroll down (quite a bit) I can see the question. 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What is the minimum/recommended RAM for Pokemon Go to run more smoothly? Deciphering the RSA encrypted message from three different public keys I have three different 1024-bit public keys with common exponent $e$ but different moduli. A message $m$ is encrypted (without padding) using the three keys, which results in three different encrypted messages.  Given the three pairs of public keys $(N_i,e)$ and the encrypted messages $c_i=m^e\bmod N_i$ , how do I decipher the original message $m$ ? Let $a,b,c>0$ such that $a+b+c=3$, find max/min of $\frac1{a^2+1}+\frac1{b^2+1}+\frac1{c^2+1}$ How to find orphaned files and images which are not linked from any css stylesheet or from any node? Is there a way to list all unused files which reside inside public file system and inside a theme directory and list them, or maybe even have an option to delete them automatically?  I mean files which are currently not linked from any css stylesheet or from any node. I have some files/directories on an external hard drive connected using USB to my Windows XP laptop. I am trying to delete those files but every time I try, I get an error "Cannot delete ....: Access Denied. Make sure disk is not full or write protected and that the file is not currently in use".  I checked that the directory is not is use. However, the permissions are set to read-only. Even if I remove the "read-only" checkbox, in Properties->Attributes, it automatically comes back again. How do I fix this? Is it a virus that is automatically changing it back to read-only?  regards,  JP Can black holes form in a finite amount of time? iOS app blocking actions with "you must join this site" message for sites I belong to I'm trying to simulate a rope (that later might get pulled on the ends*) that interacts with some obstacles. 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We can address the problem in the following way: the sum of the two variables has a density $h(x)$ given by the convolution product of the densities of the two variables, say $f$ and $g$, so that   $$ h(x) = \int_{-\infty}^{\infty} f(x-y)g(y)dy. $$  However,  $$ f(y) = g(y) = \frac{1}{\sqrt {2\pi}}\exp(-y^2/2). $$  Hence now the integral becomes:  $$ h(x) =\frac{1}{2\pi}\int_{-\infty}^{\infty}\exp(-(x-y)^2/2)\exp(-y^2/2)dy. $$  However, I am puzzled here. How should we go on from here? I cannot see how to transform this integral into the integral of a normal r.v of type $N(0,2)$. Thanks in advance for your help. How to decide which glm family to use? I have fish density data that I am trying to compare between several different collection techniques, the data has lots of zeros, and the histogram looks vaugley appropriate for a poisson distribution except that, as densities, it is not integer data. 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