Linux - Compression and Uncompression Example

compress
compress bigfile     <--------- compress bigfile to be bigfile.Z, bigfile will be disappear.
compress -r myfolder     <---------compress all file to be .Z file in myfolder
compress -c bigfile     <---------display the result to stdout
compress -c bigfile > smallfile.Z      <---------by which, unchange bigfile but saveas another compressed file(smallfile.Z).

uncompress
uncompress smallfile.Z

gzip
gzip bigfile     <--------- compress bigfile to be bigfile.gz
gzip -9 bigfile     <--------- compress bigfile to be bigfile.gz, -9 is best quality but slowest, -1 is the fastest but low compress, default is -6.
gzip -c bigfile > smallfile.gz      <--------- unchange bigfile but save as another compressed file(smallfile.gz).

gunzip
gunzip smallfile.gz     <--------- extract the gz file
gunzip -c smallfile.gz > file     <--------- extract smallfile.gz to a file,and don't smallfile.gz

zcat
zcat smallfile.gz     <---------see the file content without unzip

bzip2, bunzip2, bzcat

bzip2 default compress level 2
the usage is like gzip, gunzip, zcat
(Hints: gzip is better than compress, bzip2 is the best)



tar
option:
-c               create, write tarfile
-t                list content
-z               use gzip compress
-j               use bzip2 compress
-x              extract or restore
-v              view progress
-p              Restore the named files to their original modes, and ACLs if applicable

Example
tar -cf testfolder.tar /path/to/testfolder         <---------------Create tar file
tar -xvf testfolder.tar -C /path/to/folder         <-----------Extract tar file to another folder

Tar & gzip
tar -zpcvf testfolder.tar.gz /path/to/testfolder     <----------Tar and gzip a folder
tar -zpcvf testfolder.tar.gz --exclude=/path/to/testfolder/subfolder1 /path/to/testfolder     <----------Tar and gzip a folder except subfolder1
tar -zxvf testfolder.tar.gz -C /path/to/folder     <----------Extract the file to another
tar -ztf testfolder.tar.gz     <----------View the content

Tar & bzip2

tar -jpcvf testfolder.tar.bz2 /path/to/testfolder     <----------Tar and gzip a folder
tar -jpcvf testfolder.tar.bz2 --exclude=/path/to/testfolder/subfolder1 /path/to/testfolder     <----------Tar and bzip2 a folder except subfolder1
tar -jxvf testfolder.tar.bz2 -C /path/to/folder     <----------Extract the file to another
tar -jtf testfolder.tar.bz2     <----------View the content

dump
for example: lets backup the partition /boot
dump -S /boot                   <---------------------Show how many size will be used
dump -0uf /home/myfolder/boot.dump /boot   <-----------dump the whole partition, 0 is compress level, u means update record to /etc/dumpupdate, f is specify the file name
dump -0j -f /home/myfolder/boot.dump /boot   <-----------bump the whole partition with bzip2 compress.

restore
restore -tf /home/myfolder/boot.dump <---------------- View the dump file content
restore -rf /home/myfolder/boot.dump <---------------- Restore with dump file.