7z

Section: User Commands (1)
Updated: September 1 2006
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NAME

7z - A file archiver with highest compression ratio

SYNOPSIS

7z [adeltux] [-] [SWITCH] <ARCHIVE_NAME> <ARGUMENTS>...

DESCRIPTION

7-Zip is a file archiver with the highest compression ratio. The program supports 7z (that implements LZMA compression algorithm), LZMA2, XZ, ZIP, Zip64, CAB, RAR (if the non-free p7zip-rar package is installed), ARJ, GZIP, BZIP2, TAR, CPIO, RPM, ISO, most filesystem images and DEB formats. Compression ratio in the new 7z format is 30-50% better than ratio in ZIP format.

7z uses plugins to handle archives.

FUNCTION LETTERS

a: Add
d: Delete
e: Extract
l: List
t: Test
u: Update
x: eXtract with full paths

SWITCHES

-ai[r[-|0]]{@listfile|!wildcard}: Include archives
-ax[r[-|0]]{@listfile|!wildcard}: eXclude archives
-bd: Disable percentage indicator
-i[r[-|0]]{@listfile|!wildcard}: Include filenames
-l: don't store symlinks; store the files/directories they point to (CAUTION : the scanning stage can never end because of recursive symlinks like 'ln -s .. ldir')
-m{Parameters}: Set Compression Method (see /usr/share/doc/p7zip-full/DOCS/MANUAL/switches/method.htm for a list of methods)
-mhe=on|off: 7z format only : enables or disables archive header encryption (Default : off)
-o{Directory}: Set Output directory
-p{Password}: Set Password
-r[-|0]: Recurse subdirectories (CAUTION: this flag does not do what you think, avoid using it)
-sfx[{name}]: Create SFX archive
-si: Read data from StdIn (eg: tar cf - directory | 7z a -si directory.tar.7z)
-so: Write data to StdOut (eg: % echo foo | 7z a dummy -tgzip -si -so > /dev/null)
-slt: Sets technical mode for l (list) command
-t{Type}: Type of archive (7z, zip, gzip, bzip2 or tar. 7z format is default)
-v{Size}[b|k|m|g]: Create volumes
-u[-][p#][q#][r#][x#][y#][z#][!newArchiveName]: Update options
-w[path]: Set Working directory
-x[r[-|0]]]{@listfile|!wildcard}: Exclude filenames
-y: Assume Yes on all queries

DIAGNOSTICS

7-Zip returns the following exit codes:

0: Normal (no errors or warnings detected)
1: Warning (Non fatal error(s)). For example, some files cannot be read during compressing. So they were not compressed
2: Fatal error
7: Bad command line parameters
8: Not enough memory for operation
255: User stopped the process with control-C (or similar)

Backup and limitations

DO NOT USE the 7-zip format for backup purpose on Linux/Unix because :
- 7-zip does not store the owner/group of the file.

On Linux/Unix, in order to backup directories you must use tar :
- to backup a directory : tar cf - directory | 7za a -si directory.tar.7z
- to restore your backup : 7za x -so directory.tar.7z | tar xf -

If you want to send files and directories (not the owner of file) to others Unix/MacOS/Windows users, you can use the 7-zip format.

example : 7za a directory.7z directory

Do not use "-r" because this flag does not do what you think.

Do not use directory/* because of ".*" files (example : "directory/*" does not match "directory/.profile")

EXAMPLE 1

7z a -t7z -m0=lzma -mx=9 -mfb=64 -md=32m -ms=on archive.7z dir1: adds all files from directory "dir1" to archive archive.7z using "ultra settings"
-t7z: 7z archive
-m0=lzma: lzma method
-mx=9: level of compression = 9 (Ultra)
-mfb=64: number of fast bytes for LZMA = 64
-md=32m: dictionary size = 32 megabytes
-ms=on: solid archive = on

EXAMPLE 2

7z a -sfx archive.exe dir1: add all files from directory "dir1" to SFX archive archive.exe (Remark : SFX archive MUST end with ".exe")

EXAMPLE 3

7z a -mhe=on -pmy_password archive.7z a_directory: add all files from directory "a_directory" to the archive "archive.7z" (with data and header archive encryption on)

HTML Documentation

/usr/share/doc/p7zip-full/DOCS/MANUAL/index.htm

AUTHOR

Written for Debian by Mohammed Adnene Trojette.

7z