On Mar 29, 2014, at 1:00 PM, Paul Eggert <egg...@cs.ucla.edu> wrote:
> Tim Kientzle wrote: >> As long as it still reads the input files. > > There is no need to read input files when the input data is not used for > anything. People who want to fool tar into actually reading the files can > pipe its output to another program that discards it. I'm curious. If someone types the following command: tar cf /dev/null some files What do you think they expect to happen? I have heard of people using "tar cf /dev/null /mnt/cdrom" to test whether the files on a CD-ROM were readable. If tar "optimizes" by not reading the files, that could lead a person relying on this behavior to erroneously believe the CD-ROM had no errors. If you really believe that sending output to /dev/null should not do anything, make it a fatal error so people won't rely on it. Tim
