Compressing Files with compress


Compressing Files with compress

Compressing a file just means making it smaller so that it takes up less hard-disk space. It's like filling a toy box, closing the lid, then sitting on it to moosh the contents so that they fit into a smaller space. Any time you create a file that you'll be sending via FTP or that people will access through the Web, you'll want to compress the file so that it takes less time to send and download. As Code Listing 13.8 shows, you compress files using the compress command.

Code Listing 13.8. Listing files before and after compressing them lets you see how much smaller the new file is.

[ejr@hobbes compression]$ ls -l l* -rw-r-r-1 ejr   users   501760 Jul 27  10:06 labrea.tar [ejr@hobbes compression]$ compress  labrea.tar [ejr@hobbes compression]$ ls -l l* -rw-r-r-1 ejr   users   297027 Jul 27  10:06 labrea.tar.Z [ejr@hobbes compression]$ 

To Compress a File with compress:

  • compress labrea.tar

    At the shell prompt, type compress followed by the filename. Here, we're compressing a tarred file, which contains multiple files. As you can see in Code Listing 13.8, the compressed file has a new extension (.Z) that shows that it's compressed, and it replaces the original, uncompressed file.

Tips

  • You can compress only one file at a time. If you have multiple files you want to compress, consider archiving them first using tar, and then compressing the single archived file. See the section called Archiving with tar earlier in this chapter.

  • You can add the -c flag to compress to leave the original file untouched and send the compressed version to standard output (where you'll probably specify a name and save it to a file). For example, you might use compress -c labrea.tar > labrea.tar.Z. See Chapter 1 for some mighty interesting information on redirecting output, as is shown here.





Unix(c) Visual Quickstart Guide
UNIX, Third Edition
ISBN: 0321442458
EAN: 2147483647
Year: 2006
Pages: 251

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