Biggest.sh searches a given file system and lists the biggest files it finds in size order -- biggest first -- displaying up to 500 lines of output.  Five hundred lines of output may be a bit much, but biggest comes with a suite of options, one of which ( -l ) allows you to specify precisely how many lines you want returned.  We do exactly that with our monitoring software.  When a file system reaches alert level, we have the monitoring program call biggest.sh like this:  biggest.sh -l 10 /usr.  This returns the ten  biggest  files in /usr.

Biggest.sh has run successfully on Sun Solaris and Linux.  It is written in Bourne shell (instead of Korn or Bash) for one reason only -- portability.  The script runs under Bourne, Korn, and Bash environments without modification.

Besides the lines ( -l ) option (already shown),  biggest.sh comes with six additional options.  Here is the usage listing with a brief description of each.

      Usage: biggest.sh -fHh -l <nn> -v -t <dir> -s <nnn> fs
                        -f = Follow links
                        -H = Displays detailed documentation
                        -h = Provides usage brief
                        -l = Displays <nn> lines (default is 500)
                        -s = Minimum file size is <nnn> (default is 500K)
                        -t = Use <dir> as temp/work directory (default is /var/tmp)
                        -v = Edit (vi) file list
                        fs = Required file system argument
  

The file system specified must be a local file system. This is enforced by use of the display file systems ( df ) command  -l  or local option.  This prevents us from searching through a remotely mounted file system (a real wild goose chase!).

Description
Using the find command, biggest.sh descends through the specified file system listing all files whose sizes exceed either the default minimum size (500K) or the minimum value provided via size ( -s ) option.  The file list is created in /var/tmp by default as it usually much larger than /tmp.  However, in the event that /var is the file system that's full (or is not writable to the user), the temp dir ( -t ) option is available to redirect the output elsewhere.

When root is the directory being searched, -xdev is supplied automatically as a  find  command argument so only the root directory, and none of its subdirectories, is searched.  Without  -xdev , you can easily find a file in another directory (and possibly another file system) that is larger than the file that is actually the culprit.

Remember that a file system can fill up in other ways; for example, instead of the culprits being one or two hernia files, the real problem may be a directory with many large files, none of which is the biggest.

For that, I recommend the use of  dispus, a Perl program developed by Scott Rochford that traverses disks locating the directories that are the fullest.  Between  biggest.sh and  dispus,  if you cannot find the the offending files, then they are probably your own files and you really don't want to see them listed anyway.