Raw Input
The data file is generated by a 'tar tvf tar_file' command, where
  1. the path of an object always begins at 47th column.
  2. there may be spaces in the paths.
An example of input is as follows: 
rwxrwxr-x john/users   2205 Oct  1 11:49 2001 ./dir1/file1.txt
rwxrwxr-x john/users      0 Sep 13 10:06 2001 ./dir2/
rwxrwxr-x john/users      0 Oct  9 15:24 2001 ./dir2/dir3/
rwxrwxr-x john/users  10422 Oct  9 15:09 2001 ./dir2/dir3/file2.txt
rwxrwxr-x john/users    856 Oct  9 15:16 2001 ./dir2/dir3/file3.txt
rwxrwxr-x john/users   1020 Oct 22  8:16 2001 ./dir2/dir3/file  4.txt
Desired Output
What we want to do is to
  1. remove the lines describing directories which always end with slashes, e.g., the second and the third lines.
  2. for lines describing files, remove the directory part of its path, leaving only its basename.
The desired output is: 
rwxrwxr-x john/users   2205 Oct  1 11:49 2001 file1.txt
rwxrwxr-x john/users  10422 Oct  9 15:09 2001 file2.txt
rwxrwxr-x john/users    856 Oct  9 15:16 2001 file3.txt
rwxrwxr-x john/users   1020 Oct 22 15:16 2001 file  4.txt
Script and Comments
Script1 
[ 1] /\/$/d
[ 2] s|^\(.\{46\}\).*/\(.*\)|\1\2|