Archiving and compressingAlthough disk space isn t as much (Web site design)
Archiving and compressingAlthough disk space isn t as much of a premium as it once was, bandwidthand backup media still are. Subsequently, this group provides a potpourri oftools for compacting and organizing data for storage, as shown in Table A-1. Table A-1Archiving and Compressing ToolsCommandPurposebzip2Compresses files into .bz2format. Used mostly for incredibly large sets of text files (which is what sourcecode actually is). compressCompresses files into .Zformat. Pretty old and not used much in the Linux world. gunzipUncompresses .gzfiles and .tgzfiles. gzipCompresses files into .gzformat. tarPackages files together in a group. uncompressUncompresses files from .Z format. unzipUncompresses files from .zipformat. zipCompresses files into .zipformat. Built-in bash commandsSome commands don t even seem to exist if you try to look up their helpinformation in the manpages, and the commands don t show up as files onyour system. Remember, as you type commands at the prompt, that you recommunicating with a type of program called a shell.(In my case, it s bash, the default Linux shell.) The shell has a set of commands, included in the fol- lowing list, that you can use to communicate with it, as shown in Table A-2. Table A-2Shell CommandsCommandPurposealiasCreates command shortcuts. envLists your current environment variables and their settings. exportWhenever you re told to set an environment variable, use this first so that the variable will be remembered properly. 396Part VI: Appendixes