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diff --git a/misc/par2cmdline/par2.1 b/misc/par2cmdline/par2.1 deleted file mode 100644 index b10f5e7f09..0000000000 --- a/misc/par2cmdline/par2.1 +++ /dev/null @@ -1,284 +0,0 @@ -.\" -.\" par2(1) -.\" -.\" Copyright (C) 2004 Andres Salomon -.TH par2 1 "May 2004" -.SH NAME -par2 \- PAR 2.0 compatible file verification and repair tool. -.SH SYNOPSIS -.B par2 -c(reate) [options] <par2 file> [files] -.br -.B par2 -v(erify) [options] <par2 file> [files] -.br -.B par2 -r(epair) [options] <par2 file> [files] -.br - -.br - Or: -.br - -.br -.B par2create -[options] <par2 file> [files] -.br -.B par2verify -[options] <par2 file> [files] -.br -.B par2repair -[options] <par2 file> [files] -.SH DESCRIPTION -par2 is a program for creating and using PAR2 files to detect -damage in data files and repair them if necessary. It can be used with -any kind of file. -.SH OPTIONS -.TP -.B -b<n> -Set the Block-Count -.TP -.B -s<n> -Set the Block-Size (Don't use both -b and -s) -.TP -.B -r<n> -Level of Redundancy (%) -.TP -.B -c<n> -Recovery block count (don't use both -r and -c) -.TP -.B -f<n> -First Recovery-Block-Number -.TP -.B -u -Uniform recovery file sizes -.TP -.B -l -Limit size of recovery files (Don't use both -u and -l) -.TP -.B -n<n> -Number of recovery files (Don't use both -n and -l) -.TP -.B -m<n> -Memory (in MB) to use -.TP -.B -v [-v] -Be more verbose -.TP -.B -q [-q] -Be more quiet (-qq gives silence) -.TP -.B -- -Treat all remaining CommandLine as filenames -.TP -.BR -.SH EXAMPLES - -With PAR 2.0 you can create PAR2 recovery files for as few as 1 or as many as -32768 files. If you wanted to create PAR1 recovery files for a single file -you are forced to split the file into muliple parts and RAR is frequently -used for this purpose. You do NOT need to split files with PAR 2.0. - -To create PAR 2 recovery files for a single data file (e.g. one called -test.mpg), you can use the following command: - - par2 create test.mpg - -If test.mpg is an 800 MB file, then this will create a total of 8 PAR2 files -with the following filenames (taking roughly 6 minutes on a PC with a -1500MHz CPU): - - test.mpg.par2 - This is an index file for verification only - test.mpg.vol00+01.par2 - Recovery file with 1 recovery block - test.mpg.vol01+02.par2 - Recovery file with 2 recovery blocks - test.mpg.vol03+04.par2 - Recovery file with 4 recovery blocks - test.mpg.vol07+08.par2 - Recovery file with 8 recovery blocks - test.mpg.vol15+16.par2 - Recovery file with 16 recovery blocks - test.mpg.vol31+32.par2 - Recovery file with 32 recovery blocks - test.mpg.vol63+37.par2 - Recovery file with 37 recovery blocks - -The test.mpg.par2 file is 39 KB in size and the other files vary in size from -443 KB to 15 MB. - -These par2 files will enable the recovery of up to 100 errors totalling 40 MB -of lost or damaged data from the original test.mpg file when it and the par2 -files are posted on UseNet. - -When posting on UseNet it is recommended that you use the "-s" option to set -a blocksize that is equal to the Article size that you will use to post the -data file. If you wanted to post the test.mpg file using an article size -of 300 KB then the command you would type is: - - par2 create -s307200 test.mpg - -This will create 9 PAR2 files instead of 8, and they will be capable of -correcting up to 134 errors totalling 40 MB. It will take roughly 8 minutes -to create the recovery files this time. - -In both of these two examples, the total quantity of recovery data created -was 40 MB (which is 5% of 800 MB). If you wish to create a greater or lesser -quantity of recovery data, you can use the "-r" option. - -To create 10% recovery data instead of the default of 5% and also to use a -block size of 300 KB, you would use the following command: - - par2 create -s307200 -r10 test.mpg - -This would also create 9 PAR2 files, but they would be able to correct up to -269 errors totalling 80 MB. Since twice as much recovery data is created, it -will take about 16 minutes to do so with a 1500MHz CPU. - -The "-u" and "-n" options can be used to control exactly how many recovery -files are created and how the recovery blocks are distributed amoungst them. -They do not affect the total quantity of recovery data created. - -The "-f" option is used when you create additional recovery data. - -e.g. If you have already created 10% and want another 5% then you migh use -the following command: - - par2 create -s307200 -r5 -f300 test.mpg - -This specifies the same block size (which is a requirement for additional -recovery files), 5% recovery data, and a first block number of 300. - -The "-m" option controls how much memory par2 uses. It defaults to -16 MB unless you override it. - -CREATING PAR2 FILES FOR MULTIPLE DATA FILES - -When creating PAR2 recovery files form multiple data files, you must specify -the base filename to use for the par2 files and the names of all of the data -files. - -If test.mpg had been split into multiple RAR files, then you could use: - - par2 create test.mpg.rar.par2 test.mpg.part*.rar - -The files filename "test.mpg.rar.par2" says what you want the par2 files to -be called and "test.mpg.part*.rar" should select all of the RAR files. - -VERIFYING AND REPAIRING - -When using par2 recovery files to verify or repair the data files from -which they were created, you only need to specify the filename of one -of the par2 files to par2. - -e.g.: - - par2 verify test.mpg.par2 - -This tells par2 to use the information in test.mpg.par2 to verify the -data files. - -par2 will automatically search for the other par2 files that were -created and use the information they contain to determine the filenames -of the original data files and then to verify them. - -If all of the data files are ok, then par2 will report that repair -will not be required. - -If any of the data files are missing or damaged, par2 will report -the details of what it has found. If the recovery files contain enough -recovery blocks to repair the damage, you will be told that repair is -possible. Otherwise you will be told exactly how many recovery blocks -will be required in order to repair. - -To carry out a repair use the following command: - - par2 repair test.mpg.par2 - -This tells par2 to verify and if possible repair any damaged or -missing files. If a repair is carried out, then each file which is -repaired will be re-verified to confirm that the repair was successful. - -MISSNAMED AND INCOMPLETE DATA FILES - -If any of the recovery files or data files have the wrong filename, then -par2 will not automatically find and scan them. - -To have par2 scan such files, you must include them on the command -line when attempting to verify or repair. - -e.g.: - - par2 r test.mpg.par2 other.mpg - -This tells par2 to scan the file called other.mpg to see if it -contains any data belonging to the original data files. - -If one of the extra files specified in this way is an exact match -for a data file, then the repair process will rename the file so that -it has the correct filename. - -Because par2 is designed to be able to find good data within a -damaged file, it can do the same with incomplete files downloaded from -UseNet. If some of the articles for a file are missing, you should still -download the file and save it to disk for par2 to scan. If you -do this then you may find that you can carry out a repair in a situation -where you would not otherwise have sufficient recovery data. - -You can have par2 scan all files that are in the current directory -using a command such as: - - par2 r test.mpg.par2 * - -WHAT TO DO WHEN YOU ARE TOLD YOU NEED MORE RECOVERY BLOCKS - -If par2 determines that any of the data files are damaged or -missing and finds that there is insufficient recovery data to effect -a repair, you will be told that you need a certain number of recovery -blocks. You can obtain these by downloading additional recovery files. - -In order to make things easy, par2 files have filenames that tell you -exactly how many recovery blocks each one contains. - -Assuming that the following command was used to create recovery data: - - par2 c -b1000 -r5 test.mpg - -Then the recovery files that are created would be called: - - test.mpg.par2 - test.mpg.vol00+01.par2 - test.mpg.vol01+02.par2 - test.mpg.vol03+04.par2 - test.mpg.vol07+08.par2 - test.mpg.vol15+16.par2 - test.mpg.vol31+19.par2 - -The first file in this list does not contain any recovery data, it only -contains information sufficient to verify the data files. - -Each of the other files contains a different number of recovery blocks. -The number after the '+' sign is the number of recovery blocks and the -number preceding the '+' sign is the block number of the first recovery -block in that file. - -If par2 told you that you needed 10 recovery blocks, then you would -need "test.mpg.vol01+02.par2" and "test.mpg.vol07+08.par". You might of course -choose to fetch "test.mpg.vol15+16.par2" instead (in which case you would have -an extra 6 recovery blocks which would not be used for the repair). - -.SH NOTES - -This version of par2 does not support recording path information for -files. Whilst you can create recovery files for files from multiple locations, -it will expect all files to be in the current directory when verifying and -repairing. This limitation will be corrected in an update. - -.SH REED SOLOMON CODING - -PAR2 uses Reed Solomon Coding to perform its calculations. For details of this -coding technique try the following link: - -``A Tutorial on Reed-Solomon Coding for Fault-Tolerance in RAID-like Systems'' -<http://www.cs.utk.edu/~plank/plank/papers/CS-96-332.html> - -.SH AUTHOR -.br -.B par2 -was written by Peter Brian Clements <peterbclements@users.sourceforge.net>. - -This man page was contributed by Andres Salomon <dilinger@voxel.net> -for the Debian GNU/Linux system (but may be used by others). |