expand

expand, unexpand - expand tabs to spaces, and vice versa.

SYNTAX
      expand [-tabstop] [-tab1,tab2,...,tabn] file ...
      unexpand [-a] file ...

DESCRIPTION

     expand processes the named files or the standard input writing the standard
     output with tabs changed into blanks.  Backspace characters are preserved
     into the output and decrement the column count for tab calculations.
     expand is useful for pre-processing character files (before sorting,
     looking at specific columns, etc.) that contain tabs.

     If a single tabstop argument is given, then tabs are set tabstop spaces
     apart instead of the default 8.  If multiple tabstops are given then the
     tabs are set at those specific columns.

     unexpand puts tabs back into the data from the standard input or the
     named files and writes the result on the standard output.

Option (with unexpand only):

     -a    By default, only leading blanks and tabs are reconverted to maximal
           strings of tabs.  If the -a option is given, then tabs are inserted
           whenever they would compress the resultant file by replacing two or
           more characters.

"I would rather train someone and lose them, than not train them and keep them" - Zig Ziglar

Related commands:

tr - Translate, squeeze, and/or delete characters

Equivalent BASH command:

expand - expand tabs to spaces