Commands by ozymandias (2)

  • In my work environment, we log onto the servers as our user ('user', in the sample ouput), and 'sudo su - root' to other accounts. This trick allows us to return the account name we logged in as -- and not the account name we currently are ('root', in this example). Using this trick, you can build other commands: Set your CVSROOT env variable to your account name: CVSROOT=$(who am i | awk '{print $1}')@cvs.server.example.com:/cvsroot SCP a file to another server: scp file.txt $(who am i | awk '{print $1}')@some.other.server.com:. This works out great in my environment, as we can include this in our documentation and make the comands more easy to copy/paste for different users, and not have to set all sorts of variables, or modify the docs for each user. whoami gives you the name of the user you currently are, not the user you logged on originally as. who gives you a listing of every single person logged onto the server. who am i gives you the name of the user you logged on as, and not who you changed to with su. Look at the following scenario: whoami user su - # whoami root # who am i user pts/51 2009-02-13 10:24 (:0.0) whoami != who am i Show Sample Output


    -18
    who am i
    ozymandias · 2009-02-20 16:26:11 10
  • The expansion {,} in bash will repeat the given string once for each item seperated by commas. The given command will result in the following being run: cp /really/long/path/and/file/name /really/long/path/and/file/name-`date -I` These can be embedded as needed, ex: rm file{1,2,3{1,2,3}} would delete the files file1, file2, file31, file32, file32, and no other files.


    4
    cp /really/long/path/and/file/name{,-`date -I`}
    ozymandias · 2009-02-18 20:35:47 4

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