BSD 2.11 - man page for rev (bsd section 1)

REV(1)							      General Commands Manual							    REV(1)

NAME
       rev - reverse lines of a file

SYNOPSIS
       rev [ file ] ...

DESCRIPTION
       Rev  copies the named files to the standard output, reversing the order of characters in every line.  If no file is specified, the standard
       input is copied.

7th Edition							  April 29, 1985							    REV(1)