I recently learned about the mv -t flag option in bash, but when I checked the man pages on my computer, there was no mention of it. The man pages were dated 9 July 2002. I ssh-ed into another UNIX system and found the mv -t option in the man pages there, dated December 2015.


I reckoned my bash shell needed upgrading, so I upgraded from version 3.2.57(1) to 4.3.42(1), following the steps here: http://clubmate.fi/upgrade-to-bash-4-in-mac-os-x/

Now when I run "echo $BASH_VERSION" it says "4.3.42(1)-release", but if I do "bash --version" it returns "version 3.2.57(1)-release". The man pages are still from 2002.

Any ideas what could be going on?

  • OSX is a variant of BSD. You have to be more specific when you say "UNIX". The OSX man pages are also available online: developer.apple.com/library/mac/documentation/Darwin/Reference/… -- the mv command on the Mac does not appear to have a -t option. -t may be a GNU-specific option – glenn jackman Feb 2 '16 at 18:40
  • Note that, with homebrew, the bash you're using may not be the first bash in your $PATH. What does type -a bash tell you? – glenn jackman Feb 2 '16 at 18:41
  • After typing 'type -a bash' I get the following: bash is /bin/bash bash is /usr/local/bin/bash – berkelem Feb 2 '16 at 19:23
  • The other UNIX system is Linux. I use a Mac OSX. Is there any way of forcing Mac to use the GNU shell? – berkelem Feb 2 '16 at 19:27
  • /usr/local/bin/bash will be the homebrew bash. For GNU utils, homebrew is probably your best option – glenn jackman Feb 2 '16 at 19:29

Thanks to Glenn Jackman for helpful comments above.

The problem was due to a difference between GNU Command Line tools and OSX Command Line Tools. To solve the problem, I followed the steps at this website: https://www.topbug.net/blog/2013/04/14/install-and-use-gnu-command-line-tools-in-mac-os-x/

Now I am running bash version 4.3.42(1) and the man pages are working as I had hoped.

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