rev —
reverse the characters or lines of one or more files
rev copies one or more files to standard output,
reversing the order of characters on every line of the file, or reversing the
order of lines of the file if -l is specified. The
following options are supported:
-l,
--line- Reverse the order of the lines of the file, instead of characters.
The following operands are supported:
- file
- Specifies the name of the file to use as input.
If file is not specified or is −,
rev copies from standard input starting at the
current offset.
The following exit values are returned:
- 0
- All files copied successfully.
- >0
- One or more files did not copy.