{"id":837,"date":"2017-03-18T18:20:04","date_gmt":"2017-03-18T12:50:04","guid":{"rendered":"https:\/\/www.wikitechy.com\/technology\/?p=837"},"modified":"2017-03-29T13:21:57","modified_gmt":"2017-03-29T07:51:57","slug":"purpose-lostfound-folder-linux-unix","status":"publish","type":"post","link":"https:\/\/www.wikitechy.com\/technology\/purpose-lostfound-folder-linux-unix\/","title":{"rendered":"What is the purpose of the lost+found folder in Linux and Unix"},"content":{"rendered":"

Purpose of\u00a0 the <\/b>lost+found<\/b> folder:<\/b><\/span><\/h4>\n
    \n
  • This \u00a0directory \u00a0is for recovering files which are not properly closed due to many reason such as power failure.<\/li>\n<\/ul>\n
      \n
    • The\u00a0 lost+found<\/b> \u00a0\u00a0folder\u00a0 contains the files with no links and files to be recovered.<\/li>\n<\/ul>\n
        \n
      • Any file to be recovered is kept in this folder.\u00a0<\/b>fsck command (file system check)\u00a0is used to recover these files.<\/li>\n<\/ul>\n
          \n
        • In generally, the directory is empty; but if there is corruption, the conditions files can be recovered after\u00a0fsck\u00a0places them here.<\/li>\n<\/ul>\n
            \n
          • The\u00a0lost+found\u00a0directory (not Lost+Found) is a construct used by\u00a0fsck\u00a0when there is damage to the filesystem (not to the hardware device, but to the fs).<\/li>\n<\/ul>\n
              \n
            • Files that would normally be lost because of directory corruption would be linked in that filesystem’s\u00a0lost+found\u00a0directory by inode number.<\/li>\n<\/ul>\n
                \n
              • \u00a0If\u00a0 you lost directories or lost files or even lost devices. Each filesystem should have its own\u00a0lost+found\u00a0directory, but you influence be looking at a system with only one file system.<\/li>\n<\/ul>\n
                  \n
                • If you run\u00a0<\/b>fsck<\/b>, the filesystem<\/b> check and repair command, it find the data fragments that are not referenced anywhere in the filesystem. In particular,\u00a0fsck\u00a0might find data that looks like a complete file but doesn’t have a name on the system \u2014 an\u00a0inode<\/b>\u00a0with no corresponding file name. This data is still using up space, but it isn’t accessible by any normal means.<\/li>\n<\/ul>\n
                    \n
                  • The \u00a0fsck<\/b>\u00a0to repair the filesystem, it will back the deleted files into files. The device is, the file had a name and location once, but that information is no longer available. So\u00a0<\/b>fsck<\/b>\u00a0deposits the file in a specific directory, called\u00a0lost+found<\/b>\u00a0(after\u00a0lost and found\u00a0property).<\/li>\n<\/ul>\n
                      \n
                    • Files that appear in\u00a0lost+found\u00a0are typically files that were already unlinked (i.e. their name had been erased) but still opened by some process (so the data wasn’t erased yet) when the system halted suddenly (kernel panic or power failure). If that’s all that happened, these files were slated for deletion anyway.<\/li>\n<\/ul>\n
                        \n
                      • Files can also appear in\u00a0<\/b>lost+found<\/b>\u00a0because the filesystem<\/b> was in an inconsistent state due to a software or hardware bug. If that’s the case, it’s a way for you to find files that were lost but that the system repair managed to salvage. If\u00a0 they do they may be incomplete or out of date; it all depends how bad the filesystem damage was.<\/li>\n<\/ul>\n
                          \n
                        • On many filesystems<\/b>, the\u00a0<\/b>lost+found<\/b>\u00a0directory is a bit special because it preallocates<\/b> a bit of space for\u00a0fsck<\/b>\u00a0to deposit files there. (The space isn’t for the file data, which\u00a0fsck\u00a0leaves in place; it’s for the directory entries which\u00a0fsck\u00a0has to make up.) If you accidentally delete\u00a0lost+found,<\/b> don’t re-create it with\u00a0mkdir<\/b>, <\/b>use\u00a0mklost+found<\/b>\u00a0.<\/li>\n<\/ul>\n[ad type=”banner”]\n

                          Example<\/strong>:<\/span><\/h4>\n
                            \n
                          • In lost+found folder you find more than 10000 folders with its name as some random number prefixed with # symbol. fsck has moved my files here in this structure while running .And ,you to identify the right directory and files and move them out of lost+found. So you run \u201cfile *\u201d in lost+found to know the type of files. It lists some thing like<\/li>\n<\/ul>\n
                            bash code<\/span> <\/div> 
                                              #7479417:  directory                  #7479418:  directory                  #7479419:  directory                  #7602560:  directory                 #7603310:  MPEG sequence, v2, program multiplex                 #7603464:  JPEG image data, JFIF standard 1.02                 #7603542:  Audio file with ID3 version 2.3.0, contains: Audio file with ID3 version 2.4.0, contains: MPEG ADTS, layer III, v1, 320kbps,                   44.1   kHz,JntStereo                #7604043:  ISO 9660 CD-ROM filesystem data 'Linux Mint 9 Isadora           ' (bootable)                #7604089:  ISO 9660 CD-ROM filesystem data 'netbook-x86_64-201005242312    ' (bootable)                #7605425:  MPEG sequence, v2, program multiplex                #7605470:  MPEG sequence, v2, program multiplex                #7605484:  MPEG sequence, v2, program multiplex                 #7607478:  gzip compressed data, from Unix, last modified: Fri May 14 07:55:35 2010                #7607788:  gzip compressed data, from Unix, last modified: Tue May  4 14:16:31 2010                #7610801:  PDF document, version 1.4                #7612061:  ISO 9660 CD-ROM filesystem data 'Ubuntu 10.04 LTS amd64         ' (bootable)                #7613228:  directory                #7613583:  directory                #7613588:  directory<\/code><\/pre> <\/div>\n
                              \n
                            • Then you filtered out all files except \u201cdirectory\u201d using \u201cfile * | grep directory > \/root\/list.dir\u201d command.<\/li>\n<\/ul>\n
                                \n
                              • \u00a0Edited \/root\/list.dir to make it as script to show the list of files in each directory with directory name. Here is a snippet of my script.<\/li>\n<\/ul>\n
                                 
                                 bash code<\/span> <\/div> 
                                              set -v               ls -l \\#10104455               ls -l \\#10104531               ls -l \\#10104536<\/code><\/pre> <\/div>\n
                                  \n
                                • The \u201cset -v\u201d will help you to echo the command the shell execute. \u201cchmod +x list.dir\u201d to make it executable.<\/li>\n<\/ul>\n
                                    \n
                                  • Now run the script in \/home\/lost+found folder, redirecting the output to \/tmp\/ (\u201c.\/list.dir 1> \/tmp\/dir.out 2>&1\u201c). Now search for your known file in dir.out output file. Now\u00a0 searched for \u201cDesktop\u201d and found some thing like this..<\/li>\n<\/ul>\n
                                     
                                     bash code<\/span> <\/div> 
                                    ls -l \\#7733249total 5704drwxr-xr-x 2 1002 1002    4096 2010-06-05 13:24 Desktopdrwxr-xr-x 2 1002 1002    4096 2010-04-30 09:15 Documentsdrwxr-xr-x 2 1002 1002    4096 2010-04-30 09:15 Downloads-rw-r--r-- 1 1002 1002     179 2010-04-30 09:14 examples.desktopdrwxr-xr-x 2 1002 1002    4096 2010-04-30 09:15 Musicdrwxr-xr-x 2 1002 1002    4096 2010-04-30 09:15 Picturesdrwxr-xr-x 2 1002 1002    4096 2010-04-30 09:15 Public-rw-r--r-- 1 1002 1002 5794003 2010-05-15 11:00 scrap001_a.oradrwxr-xr-x 2 1002 1002    4096 2010-04-30 09:15 Templates-rw-r--r-- 1 1002 1002    1265 2010-05-20 14:35 tinda chutenydrwxrwxr-x 2 1002 1002    4096 2010-05-23 14:57 Ubuntu Onedrwxr-xr-x 2 1002 1002    4096 2010-04-30 09:15 Videos<\/code><\/pre> <\/div>\n[ad type=”banner”]\n","protected":false},"excerpt":{"rendered":"
                                    Purpose of\u00a0 the lost+found folder: This \u00a0directory \u00a0is for recovering files which are not properly closed due to many reason such as power failure. The\u00a0 lost+found \u00a0\u00a0folder\u00a0 contains the files with no links and files to be recovered. Any file to be recovered is kept in this folder.\u00a0fsck command (file system check)\u00a0is used to recover […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1699,1331],"tags":[1570,1571,1568,1562,1566,1578,1567,1565,1564,1563,1561,1569,1573,1575,1572,1576,1574,1577],"class_list":["post-837","post","type-post","status-publish","format-standard","hentry","category-linux","category-unix","tag-can-you-have-multiple-lost-and-found-directories","tag-file-missing-after-fsck","tag-knowledge-basewhat-is-the-lostfound-directory","tag-linux-lostfound-delete","tag-lost-found-netflix","tag-lost-folder-from-mnt-and-recovering","tag-lost-found-meaning","tag-lostfound-ext4","tag-lostfound-folder-mac","tag-mklostfound","tag-newly-created-disk","tag-purpose-of-the-lostfound-folder-in-linux-and-unix","tag-restore-from-lostfound","tag-unix-equivalent-of-smart-folders","tag-what-are-the-advantages-disadvantages-linux-file-hierarchy-has-compared-to-other-oss","tag-what-is-the-reasoningdesign-choice-behind-the-unixlinux-file-system-structure","tag-why-do-people-choose-different-file-systems-for-different-directories","tag-why-is-the-directory-lostfound-16k-instead-of-4k-bytes"],"_links":{"self":[{"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/posts\/837","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/comments?post=837"}],"version-history":[{"count":0,"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/posts\/837\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/media?parent=837"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/categories?post=837"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/tags?post=837"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}