Thanks for your note. I don't really know where to find the "real" rev utility, but it's so darn simple that I whipped out a rudimentary C version of it for you. In case you, the reader, doesn't know what this amusing little utility does, it reverses the order of characters in a line, so Wicked Cool would become looC dekciW.

Before I present the code, I want to invite people to pop over to my business weblog The Intuitive Life, where Sun Microsystems President Jonathan Schwartz and I are currently discussing the state of Solaris and the future of Solaris 10 in the topic Sun complains, IBM won't port apps to Solaris 10. Please feel free to add your own comments about Solaris and Sun's worldwide strategy there too!

Here's the rev program, in C:

/** rudimentary version of rev.c that only works with pipes **/

#include <stdio.h>

main()
{
    char  linebuffer[1024];   
    int   i;

        while (fgets(linebuffer, 1024, stdin) != NULL) {
          for (i=strlen(linebuffer)-1; i >= 0; i--)
            putchar(linebuffer[i]);
        }
        putchar('\n');
}

The real rev program can also accept filenames, but since I only use rev in pipes in the book, I figured that this version should cover your needs. To compile and create a runnable binary, copy and paste the above into a text editor, then save it as "rev.c". Now do this:

$ cc rev.c -o rev
$ echo "alias rev=$PWD/rev" >> ~/.profile
$

This will give you a runnable program and add an alias for 'rev' to your .profile (I assume you're using Bash as your login shell) so that when you log in in the future, you'll be able to just type "rev" and get to your binary. You could also move it into a directory that's in your PATH (I use ~/bin for my own custom apps, for example), which is probably a better solution, but slightly more complicated.

That should get you going. When it's working you can do delightful and useful things like this:

$ ls -l | rev | head -5

706 latot
/TDA 05:10 02 ceD 215     resuv  tnitd 2  x-rx-rxwrd
/29.0-tniL-LMTH 2002  12 yaM 215     resuv  tnitd 6  x-rx-rxwrd
/liaM 12:41 82 ceD 215     resuv  tnitd 2  ------xwrd

Ahhh... ain't the command line grand?! :-)