WYNTK: UNIX System Admininistrator

You can look at how much disk space your files take up.

How do you find out how much space you’re using up? Most users don’t think in terms of disk space, but in terms of files and directories. You know some files are bigger than others, but it’s hard to get perspective on how big a drop they are in the ocean of disk space.

To be a good citizen, you should start paying attention to how much disk space you use up. As most users already know, you can find out how big files are by running ls —l:

% ls -l
total 139
-rw-r----1 lmui 2769    Mar 31 11:54  author_copy
-rw-r--r-1 lmui 2163514 Sep 16 1993   ch07.ps
-rw------1 lmui 18216   Sep 19 13:22  dead.letter
-rw-rw---1 lmui 20181   May 13 12:14  mbox
-rw-r----1 lmui 743     Aug 30 09:58  people
-rw------1 lmui 13378   Jun 16 14:29  tmpmail

The size of the file is shown in number of characters (or bytes).

You don’t have to know a kilobyte from a megabyte to do some rough comparisons

A twenty-line ASCII mail message is somewhere around 500 bytes, or 1/2000th of a megabyte.

A 300-page book might be 1 megabyte in ASCII form, 1 megabyte in troff form, 3 megabytes in FrameMaker, and 20 megabytes in PostScript.

A scanned-in GIF picture of your favorite television personality might be 50,000 bytes, or 1/20 of a megabyte. The PostScript version of the same picture might be half a megabyte. A picture scanned in at higher resolution will be much larger.

A 1—minute sound clip of your favorite band might be half a megabyte.

You don’t have to understand anything about bytes or ...