Mercurial > vim
annotate runtime/doc/recover.txt @ 2267:c08f91142c41 vim73
Crypt the swapfile.
| author | Bram Moolenaar <bram@vim.org> |
|---|---|
| date | Mon, 21 Jun 2010 06:15:46 +0200 |
| parents | 7c8c7c95a865 |
| children | 12b829477c60 |
| rev | line source |
|---|---|
|
2154
7c8c7c95a865
First step in the Vim 7.3 branch. Changed version numbers.
Bram Moolenaar <bram@zimbu.org>
parents:
2033
diff
changeset
|
1 *recover.txt* For Vim version 7.3a. Last change: 2009 Apr 18 |
| 7 | 2 |
| 3 | |
| 4 VIM REFERENCE MANUAL by Bram Moolenaar | |
| 5 | |
| 6 | |
| 7 Recovery after a crash *crash-recovery* | |
| 8 | |
| 9 You have spent several hours typing in that text that has to be finished | |
| 10 next morning, and then disaster strikes: Your computer crashes. | |
| 11 | |
| 12 DON'T PANIC! | |
| 13 | |
| 14 You can recover most of your changes from the files that Vim uses to store | |
| 15 the contents of the file. Mostly you can recover your work with one command: | |
| 16 vim -r filename | |
| 17 | |
| 18 1. The swap file |swap-file| | |
| 19 2. Recovery |recovery| | |
| 20 | |
| 21 ============================================================================== | |
| 22 1. The swap file *swap-file* | |
| 23 | |
| 24 Vim stores the things you changed in a swap file. Using the original file | |
| 25 you started from plus the swap file you can mostly recover your work. | |
| 26 | |
| 27 You can see the name of the current swap file being used with the command: | |
| 28 | |
| 29 :sw[apname] *:sw* *:swapname* | |
| 30 | |
| 31 The name of the swap file is normally the same as the file you are editing, | |
| 32 with the extension ".swp". | |
| 33 - On Unix, a '.' is prepended to swap file names in the same directory as the | |
| 34 edited file. This avoids that the swap file shows up in a directory | |
| 35 listing. | |
| 36 - On MS-DOS machines and when the 'shortname' option is on, any '.' in the | |
| 37 original file name is replaced with '_'. | |
| 38 - If this file already exists (e.g., when you are recovering from a crash) a | |
| 39 warning is given and another extension is used, ".swo", ".swn", etc. | |
| 40 - An existing file will never be overwritten. | |
| 41 - The swap file is deleted as soon as Vim stops editing the file. | |
| 42 | |
| 43 Technical: The replacement of '.' with '_' is done to avoid problems with | |
| 44 MS-DOS compatible filesystems (e.g., crossdos, multidos). If Vim | |
| 45 is able to detect that the file is on an MS-DOS-like filesystem, a | |
| 46 flag is set that has the same effect as the 'shortname' option. | |
| 47 This flag is reset when you start editing another file. | |
| 48 *E326* | |
| 49 If the ".swp" file name already exists, the last character is | |
| 50 decremented until there is no file with that name or ".saa" is | |
| 51 reached. In the last case, no swap file is created. | |
| 52 | |
| 53 By setting the 'directory' option you can place the swap file in another place | |
| 54 than where the edited file is. | |
| 55 Advantages: | |
| 56 - You will not pollute the directories with ".swp" files. | |
| 57 - When the 'directory' is on another partition, reduce the risk of damaging | |
| 58 the file system where the file is (in a crash). | |
| 59 Disadvantages: | |
| 60 - You can get name collisions from files with the same name but in different | |
| 61 directories (although Vim tries to avoid that by comparing the path name). | |
| 62 This will result in bogus ATTENTION warning messages. | |
| 63 - When you use your home directory, and somebody else tries to edit the same | |
| 9 | 64 file, he will not see your swap file and will not get the ATTENTION warning |
| 7 | 65 message. |
| 66 On the Amiga you can also use a recoverable ram disk, but there is no 100% | |
| 67 guarantee that this works. Putting swap files in a normal ram disk (like RAM: | |
| 68 on the Amiga) or in a place that is cleared when rebooting (like /tmp on Unix) | |
| 69 makes no sense, you will lose the swap file in a crash. | |
| 70 | |
| 71 If you want to put swap files in a fixed place, put a command resembling the | |
| 72 following ones in your .vimrc: | |
| 73 :set dir=dh2:tmp (for Amiga) | |
| 74 :set dir=~/tmp (for Unix) | |
| 75 :set dir=c:\\tmp (for MS-DOS and Win32) | |
| 76 This is also very handy when editing files on floppy. Of course you will have | |
| 77 to create that "tmp" directory for this to work! | |
| 78 | |
| 79 For read-only files, a swap file is not used. Unless the file is big, causing | |
| 80 the amount of memory used to be higher than given with 'maxmem' or | |
| 81 'maxmemtot'. And when making a change to a read-only file, the swap file is | |
| 82 created anyway. | |
| 83 | |
| 84 The 'swapfile' option can be reset to avoid creating a swapfile. | |
| 85 | |
| 86 | |
| 87 Detecting an existing swap file ~ | |
| 88 | |
| 89 You can find this in the user manual, section |11.3|. | |
| 90 | |
| 91 | |
| 92 Updating the swapfile ~ | |
| 93 | |
| 94 The swap file is updated after typing 200 characters or when you have not | |
| 95 typed anything for four seconds. This only happens if the buffer was | |
| 96 changed, not when you only moved around. The reason why it is not kept up to | |
| 97 date all the time is that this would slow down normal work too much. You can | |
| 98 change the 200 character count with the 'updatecount' option. You can set | |
| 99 the time with the 'updatetime' option. The time is given in milliseconds. | |
| 100 After writing to the swap file Vim syncs the file to disk. This takes some | |
| 101 time, especially on busy Unix systems. If you don't want this you can set the | |
| 102 'swapsync' option to an empty string. The risk of losing work becomes bigger | |
| 103 though. On some non-Unix systems (MS-DOS, Amiga) the swap file won't be | |
| 104 written at all. | |
| 105 | |
| 106 If the writing to the swap file is not wanted, it can be switched off by | |
| 107 setting the 'updatecount' option to 0. The same is done when starting Vim | |
| 108 with the "-n" option. Writing can be switched back on by setting the | |
| 109 'updatecount' option to non-zero. Swap files will be created for all buffers | |
| 110 when doing this. But when setting 'updatecount' to zero, the existing swap | |
| 111 files will not be removed, it will only affect files that will be opened | |
| 112 after this. | |
| 113 | |
| 114 If you want to make sure that your changes are in the swap file use this | |
| 115 command: | |
| 116 | |
| 117 *:pre* *:preserve* *E313* *E314* | |
| 118 :pre[serve] Write all text for all buffers into swap file. The | |
| 164 | 119 original file is no longer needed for recovery. |
| 120 This sets a flag in the current buffer. When the '&' | |
| 121 flag is present in 'cpoptions' the swap file will not | |
| 122 be deleted for this buffer when Vim exits and the | |
| 123 buffer is still loaded |cpo-&|. | |
| 124 {Vi: might also exit} | |
| 7 | 125 |
| 126 A Vim swap file can be recognized by the first six characters: "b0VIM ". | |
| 127 After that comes the version number, e.g., "3.0". | |
| 128 | |
| 593 | 129 |
| 130 Links and symbolic links ~ | |
| 131 | |
| 132 On Unix it is possible to have two names for the same file. This can be done | |
| 133 with hard links and with symbolic links (symlinks). | |
| 134 | |
| 135 For hard links Vim does not know the other name of the file. Therefore, the | |
| 136 name of the swapfile will be based on the name you used to edit the file. | |
| 137 There is no check for editing the same file by the other name too, because Vim | |
| 138 cannot find the other swapfile (except for searching all of your harddisk, | |
| 139 which would be very slow). | |
| 140 | |
| 141 For symbolic links Vim resolves the links to find the name of the actual file. | |
| 142 The swap file name is based on that name. Thus it doesn't matter by what name | |
| 143 you edit the file, the swap file name will normally be the same. However, | |
| 144 there are exceptions: | |
| 145 - When the directory of the actual file is not writable the swapfile is put | |
| 146 elsewhere. | |
| 147 - When the symbolic links somehow create a loop you get an *E773* error | |
| 148 message and the unmodified file name will be used. You won't be able to | |
| 149 save your file normally. | |
| 150 | |
| 7 | 151 ============================================================================== |
| 152 2. Recovery *recovery* *E308* *E311* | |
| 153 | |
| 154 Basic file recovery is explained in the user manual: |usr_11.txt|. | |
| 155 | |
| 156 Another way to do recovery is to start Vim and use the ":recover" command. | |
| 157 This is easy when you start Vim to edit a file and you get the "ATTENTION: | |
| 158 Found a swap file ..." message. In this case the single command ":recover" | |
| 159 will do the work. You can also give the name of the file or the swap file to | |
| 160 the recover command: | |
| 161 *:rec* *:recover* *E305* *E306* *E307* | |
| 162 :rec[over] [file] Try to recover [file] from the swap file. If [file] | |
| 163 is not given use the file name for the current | |
| 164 buffer. The current contents of the buffer are lost. | |
| 165 This command fails if the buffer was modified. | |
| 166 | |
| 167 :rec[over]! [file] Like ":recover", but any changes in the current | |
| 168 buffer are lost. | |
| 169 | |
| 170 *E312* *E309* *E310* | |
| 171 Vim has some intelligence about what to do if the swap file is corrupt in | |
| 172 some way. If Vim has doubt about what it found, it will give an error | |
| 173 message and insert lines with "???" in the text. If you see an error message | |
| 174 while recovering, search in the file for "???" to see what is wrong. You may | |
| 175 want to cut and paste to get the text you need. | |
| 176 | |
| 177 The most common remark is "???LINES MISSING". This means that Vim cannot read | |
| 178 the text from the original file. This can happen if the system crashed and | |
| 179 parts of the original file were not written to disk. | |
| 180 | |
| 181 Be sure that the recovery was successful before overwriting the original | |
| 182 file or deleting the swap file. It is good practice to write the recovered | |
| 183 file elsewhere and run 'diff' to find out if the changes you want are in the | |
|
2033
de5a43c5eedc
Update documentation files.
Bram Moolenaar <bram@zimbu.org>
parents:
1702
diff
changeset
|
184 recovered file. Or use |:DiffOrig|. |
| 7 | 185 |
| 186 Once you are sure the recovery is ok delete the swap file. Otherwise, you | |
| 187 will continue to get warning messages that the ".swp" file already exists. | |
| 188 | |
| 189 {Vi: recovers in another way and sends mail if there is something to recover} | |
| 190 | |
| 2267 | 191 |
| 192 ENCRYPTION AND THE SWAP FILE *:recover-crypt* | |
| 193 | |
| 194 When the text file is encrypted the swap file is encrypted as well. This | |
| 195 makes recovery a bit more complicated. When recovering from a swap file and | |
| 196 encryption has been used, you will be asked to enter one or two crypt keys. | |
| 197 | |
| 198 If the text file does not exist you will only be asked to enter the crypt key | |
| 199 for the swap file. | |
| 200 | |
| 201 If the text file does exist, it may be encrypted in a different way than the | |
| 202 swap file. You will be asked for the crypt key twice: | |
| 203 | |
| 204 Need encryption key for "/tmp/tt" ~ | |
| 205 Enter encryption key: ****** ~ | |
| 206 "/tmp/tt" [crypted] 23200L, 522129C ~ | |
| 207 Using swap file "/tmp/.tt.swp" ~ | |
| 208 Original file "/tmp/tt" ~ | |
| 209 Swap file is encrypted: "/tmp/.tt.swp" ~ | |
| 210 If you entered a new crypt key but did not write the text file, ~ | |
| 211 enter the new crypt key. ~ | |
| 212 If you wrote the text file after changing the crypt key press enter ~ | |
| 213 to use the same key for text file and swap file ~ | |
| 214 Enter encryption key: ~ | |
| 215 | |
| 216 You can be in one of these two situations: | |
| 217 | |
| 218 1. The encryption key was not changed, or after changing the key the text file | |
| 219 was written. You will be prompted for the crypt key twice. The second | |
| 220 time you can simply press Enter. That means the same key is used for the | |
| 221 text file and the swap file. | |
| 222 2. You entered a new encryption key, but did not save the text file. Vim will | |
| 223 then use the new key for the swap file, and the text file will still be | |
| 224 encrypted with the old key. At the second prompt enter the new key. | |
| 225 | |
| 226 Note that after recovery the key of the swap file will be used for the text | |
| 227 file. Thus if you write the text file, you need to use that new key. | |
| 228 | |
| 229 | |
| 7 | 230 vim:tw=78:ts=8:ft=help:norl: |