Expand/Unexpand Tabs

Usage:  tabs [-hua-] [-<tabs>][ file1 file2 ... ]

   tabs expands tab characters into spaces or, if -u is
   specified, unexpands spaces into tabs as it copies the
   input files to stdout.  If no files are given, tab reads
   from stdin.  If multiple files are given, they're concat-
   enated one after the other to stdout.

   When unexpanding, only leading white space is normally
   converted to tabs.  If -a is specified, tabs are inserted
   anywhere they would replace two or more characters.

Options:

   -h         Help.  (This screen.)
   -u         Unexpand tabs.
   -a         Unexpand all tabs.
   -<tabs>    Tab settings to use for viewing text.  Default is
              to use value given by the TABS environment variable
              or, if  that's undefined, to assume tabstops every
              8 characters.  If desired, a list of tabstops can
              specified, separated by commas; the difference
              between the last two tabs given is used a standard
              increment for following tabs.
   --         End of options.