securely overwrite a file with random junk, rename it to clear the directory entry and finally delete it

$ shred -vzu /tmp/junk-file-to-be-shredded
shred: /tmp/junk-file-to-be-shredded: pass 1/26 (random)...
shred: /tmp/junk-file-to-be-shredded: pass 2/26 (dddddd)...
shred: /tmp/junk-file-to-be-shredded: pass 3/26 (bbbbbb)...
shred: /tmp/junk-file-to-be-shredded: pass 4/26 (333333)...
shred: /tmp/junk-file-to-be-shredded: pass 5/26 (249249)...
shred: /tmp/junk-file-to-be-shredded: pass 6/26 (eeeeee)...
shred: /tmp/junk-file-to-be-shredded: pass 7/26 (cccccc)...
shred: /tmp/junk-file-to-be-shredded: pass 8/26 (888888)...
shred: /tmp/junk-file-to-be-shredded: pass 9/26 (ffffff)...
shred: /tmp/junk-file-to-be-shredded: pass 10/26 (666666)...
shred: /tmp/junk-file-to-be-shredded: pass 11/26 (555555)...
shred: /tmp/junk-file-to-be-shredded: pass 12/26 (777777)...
shred: /tmp/junk-file-to-be-shredded: pass 13/26 (random)...
shred: /tmp/junk-file-to-be-shredded: pass 14/26 (444444)...
shred: /tmp/junk-file-to-be-shredded: pass 15/26 (db6db6)...
shred: /tmp/junk-file-to-be-shredded: pass 16/26 (b6db6d)...
shred: /tmp/junk-file-to-be-shredded: pass 17/26 (000000)...
shred: /tmp/junk-file-to-be-shredded: pass 18/26 (999999)...
shred: /tmp/junk-file-to-be-shredded: pass 19/26 (492492)...
shred: /tmp/junk-file-to-be-shredded: pass 20/26 (aaaaaa)...
shred: /tmp/junk-file-to-be-shredded: pass 21/26 (924924)...
shred: /tmp/junk-file-to-be-shredded: pass 22/26 (6db6db)...
shred: /tmp/junk-file-to-be-shredded: pass 23/26 (222222)...
shred: /tmp/junk-file-to-be-shredded: pass 24/26 (111111)...
shred: /tmp/junk-file-to-be-shredded: pass 25/26 (random)...
shred: /tmp/junk-file-to-be-shredded: pass 26/26 (000000)...
shred: /tmp/junk-file-to-be-shredded: removing
shred: /tmp/junk-file-to-be-shredded: renamed to /tmp/000000000000000000000000
shred: /tmp/000000000000000000000000: renamed to /tmp/00000000000000000000000
shred: /tmp/00000000000000000000000: renamed to /tmp/0000000000000000000000
shred: /tmp/0000000000000000000000: renamed to /tmp/000000000000000000000
shred: /tmp/000000000000000000000: renamed to /tmp/00000000000000000000
shred: /tmp/00000000000000000000: renamed to /tmp/0000000000000000000
shred: /tmp/0000000000000000000: renamed to /tmp/000000000000000000
shred: /tmp/000000000000000000: renamed to /tmp/00000000000000000
shred: /tmp/00000000000000000: renamed to /tmp/0000000000000000
shred: /tmp/0000000000000000: renamed to /tmp/000000000000000
shred: /tmp/000000000000000: renamed to /tmp/00000000000000
shred: /tmp/00000000000000: renamed to /tmp/0000000000000
shred: /tmp/0000000000000: renamed to /tmp/000000000000
shred: /tmp/000000000000: renamed to /tmp/00000000000
shred: /tmp/00000000000: renamed to /tmp/0000000000
shred: /tmp/0000000000: renamed to /tmp/000000000
shred: /tmp/000000000: renamed to /tmp/00000000
shred: /tmp/00000000: renamed to /tmp/0000000
shred: /tmp/0000000: renamed to /tmp/000000
shred: /tmp/000000: renamed to /tmp/00000
shred: /tmp/00000: renamed to /tmp/0000
shred: /tmp/0000: renamed to /tmp/000
shred: /tmp/000: renamed to /tmp/00
shred: /tmp/00: renamed to /tmp/0
shred: /tmp/junk-file-to-be-shredded: removed