Archiving and Compression go well together. After some background stuff, this presentation will demo and compare some gui tools and operations on tarballs and zipfiles.

Terminology and Background

Archiving = combining multiple files in one

• for convenience .. transport (eg, email), access (eg linking)
• for association -- versioning, simple-minded backup
• some (pure) archive formats: .a .ar .cpio .shar .tar

Compression = (in this context) lossless size reduction

• by removing (well, abbreviating) redundancy
• by custom re-encoding
• some common compression formats .Z .gz .bz2

Compressed Archive: (any) archive + (any) compression

• eg: .tar.gz (or .tgz) .tar.bz2 .cpio.gz
• efficient compression but inconvenient for updating (although gui tools hide the inconvenience, prob. w/ performance cost)

Compressing-Archiver: stores each component compressed

• older: .arc .pak .arj .zoo .lzh
• newer(?) .zip .rar .jar .cab
• updatable components but less efficient compression

Additional Background and General Remarks

• self-validating integrity (eg, checksums)
• file corruption risk -- be aware
• unequal compressability (sometimes even negative)
• http://en.wikipedia.org/wiki/List_of_archive_formats
• as wikipedia points out, packages (eg .deb .rpm) may be yet another archive category, but we will leaver that for another day.
• other local references: ArchivingAndCompression (roadmap)

Linux Tools

Traditional command line tools (here, for reference, only)

• tar, cpio, same with gzip or bzip2, zip

Gui Tools .. file manager built-ins

Note that drag and drop may behave different in gnome-based and kde-based apps, and drag & drop across the gnome-kde fence is often not even possible.

• nautilus
  • supports several formats (+ hokey email sendto)
  • creation: not bad. allows choosing destdir
  • extraction: may create unwanted _FILES topdir
  • viewing (eg, double-click) launches file-roller
• Konqueror
  • built-in viewer, supports drag & drop extraction (only)
  • has open-with chhoices for Ark (and KArchiver?, if installed)

Gui Tools .. dedicated

• file-roller (v2.14.3) .. standard gnome
  • can launch from nautilus (only if archive exists)
  • good file-manager-like features: select, view/open. View one dir at a time, but gui dir navigation is intuitive (back/up)
  • good extract-to destdir control, a few useful options
  • View/View all files may be a convenience, but *be sure to reset to View as a folder before exiting, or you may think program has broken (loses subdirs)
  • allows (emulates) update even on compressed archives
  • Open destination folder after extraction always errs?
  • location bar may have extraneous/misleading info
  • drag & drop extract to konqueror works!
• ark (v2.6.3) .. std kde
  • nice file tree display, but may contain some surprises (see next)
  • drag & drop a into an archive always goes to the topmost dir, ugh!
• karchiver (v3.4.0-rc1) kde separate install
  • http://freshmeat.net/projects/karchiveur/ .. see review
  • http://perso.orange.fr/coquelle/karchiver/ .. homepage/download
  • seems to have lots (too many?) of features and configurability, but the basic file-manager-like behavior annoyed me (could only view one directory, and navigation back was via drop-down list). Drag & Drop (from konqueror) seems seriously broke. Some of the features seem neat at first glance (eg, conversion of archive type), but have a crude and/or awkward user interface. I've also found features that do not seem to do anything (encrypt) and others that do unexpected things.
• xarchiver (v0.3.9.2beta2) .. xfce and/or separate install
  • http://freshmeat.net/projects/xarchiver/ .. small summary
  • http://xarchiver.xfce.org/ .. homapage/download
  • all-in-one file viewer (only) shows full-paths but doesn't meet gui directory structure expectations. prevents versatile drag & drop.
  • interestingly, does drag & drop with both gnome & kde, but flat file listing seriously limits usefulness of adding/updating archives. Hmmm, drag & drop works only with creating. extraction seems only to work via button & dialog.

Final Remarks

Recommendations

• for max compression, consider tar.bz2
• for max portability, consider tar.gz
• for max updatability, consider zip
• with gui tools. try to create images of an existing filetree in one shot, because dragging-into or otherwise adding to a specific subdir in an archive is difficult to control.
• If you have to add to an archive, use file-roller, and furthermore, try to do this only with zips.

Tips

• dedicated archive manager programs give more control than file manager built-in capabilites
• for custom (eg filelist) operations, the cmdline rules
• extraction: pay attention to destination dir
• for viewing archive contents, ark has the nicest tree display, very nice stats, and a nice search tool.

Disclaimer

These observations do not claim to be the result of exhaustive or even carefully-performed comparisons. Please take them as a subjective quick-view, and factor in your own experiences as well as other evaluations and recommendations.

Hopefuly, this short coverage will nevertheless provide some orientation for those approaching archive management operations without prior exposure.