Slightly edited version of the chat comment made during the class of April 16,2020


from Zhilin Yang to Everyone:    1:03  PM
A quick question. Do we have to install Ubuntu from Microsoft store? Can I install Ubuntu Desktop from the Ubuntu website?
     
     from Zhilin Yang to Everyone:    1:05  PM
     Microsoft store is blocked by IT as well
     
     from Ramiro Iglesias-Bartolome (internal) to Everyone:    1:05  PM
     I think it is a great idea to give one more week to catch up!
     
     from Joanna Thomas to Everyone:    1:05  PM
     I installed everything ok but wouldn't mind an extra week to practice Unix if others need more time
     
     from Sandeep Gurram to Everyone:    1:06  PM
     Same, Its nice to get a little more time to get used to the commands
     
     from Zhilin Yang to Everyone:    1:06  PM
     Then can we use our personal PC to finish this class?
     
     from ping xue to Everyone:    1:06  PM
     it is ok to stay in Chapter III Unix commend line for one more week. Thanks!
     
     from Monika Mehta (internal) to Everyone:    1:06  PM
     Sure, extra week to finish working on unix would be great.
     
     from Mariam Malik (internal) to Everyone:    1:06  PM
     would love an extra week. feeling a little rushed at this point.
     
     from Mariam Malik (internal) to Everyone:    1:07  PM
     do mac users have to send the decal as well? 
     
     from Devon Atkinson to Everyone:    1:07  PM
     I was contacted by IT this morning - NCI Frederick had their own install methods working around to install ubuntu
      without windows store (not sure how - there was a folder on a server they use) and had to re-add Java. 
      I was able to do this weeks lesson on my home computer, but I am fine delaying so that others can catch up. 

from Monika Mehta (internal) to Everyone:    1:10  PM
My question - how do you get the command prompt back on the terminal once you are in, say the man command for something.
I was also stuck without the command prompt when I entered wc without a file name

     from Des to Everyone:    1:11  PM
     you can just type "q" to exit a man page; 
      
from Sandeep Gurram to Everyone:    1:11  PM
Also, how do you force cancel a command

     from Des to Everyone:    1:12  PM
     for getting stuck without the command prompt (i.e. wc without a filename) or 
      to force cancel a command type and hold the "ctrl" key and press "c"


from ping xue to Everyone:    1:26  PM
cd can only change to one directory at one time? 

     Verbal answer:
     Correct - you can only "exist in a single directory at a time"
      
from Jeffrey Hanson to Everyone:    1:26  PM
what do -rw-r--r-r stand for?

     from Carl McIntosh to Everyone:    1:27  PM
     r stands for read permssions 

     from Carl McIntosh to Everyone:    1:27  PM
     w for write

from Monika Mehta (internal) to Everyone:    1:31  PM
can we move files to directory above the current directory?

     Verbal answer:
      yes you can move files above the current directory by referring to it as "../"  e.g. cp file1 file2 ../

from Jerico Santos to Everyone:    1:32  PM
how can you move multiple files into a single directory

     Verbal answer:
      yes you can move files above the current directory by referring to it as "../"  e.g. cp file1 file2 diretory
      
from Zhilin Yang to Everyone:    1:39  PM
Can I use vim instead of nano?

     from Des to Everyone:    1:41  PM
     zhilin - yes, you can use vim if you want (i prefer emacs).

from Carl McIntosh to Everyone:    1:39  PM
touch just creates the an empty file with the name

from Zhilin Yang to Everyone:    1:43  PM
is there 'undo' command in unix? 

     from Carl McIntosh to Everyone:    1:43  PM
     no undo after issuing the command

from Monika Mehta (internal) to Everyone:    1:44  PM
how are more and less different from head and tail?

     from Carl McIntosh to Everyone:    1:45  PM
     less and more allow paging (screen full)

     from Carl McIntosh to Everyone:    1:45  PM
     less allows paging using the space bar

from Zhilin Yang to Everyone:    1:46  PM
Then if I accidently delete a folder, is there a way to make up? Thanks

     from Carl McIntosh to Everyone:    1:46  PM
     Yang, not on your local computer, but in biowulf and helix you can recover at some level

     rom Zhilin Yang to Everyone:    1:47  PM
     Biowulf doesn't backup the files right?

     from Carl McIntosh to Everyone:    1:47  PM
     on a day, and week level

     from Des to Everyone:    1:48  PM
     backups on biowulf: https://hpc.nih.gov/storage/backups.html

     from Zhilin Yang to Everyone:    1:49  PM
     Hi @Des, I read that page before. Most of the data is in the Data directory and that is not backuped

     from Des to Everyone:    1:53  PM
     Zhilin - yes, not backed up, but it's not deleted until after some time ("Recover files in data directory from snapshot")

from Jerico Santos to Everyone:    1:47  PM
why have a separate command for remove and rmdir?

from Jerico Santos to Everyone:    1:49  PM
can you use rm to remove directory with files in it? maybe that;s the reason why (thought about it just now.)

     Verbal answer:
      you can use rm to remove a whole directory and its files by using the recursive argument 'rm -r directory'

from Yunlong He to Everyone:    1:52  PM
How to set up the $ sign start on a new line? my $ sign is just flowing my user name and folder name. They are on the same line.

     from Carl McIntosh to Everyone:    1:53  PM
     Yunlong, PS1="$ "

     from Des to Everyone:    1:54  PM
     Yunlong -- it's a setting that you can customize in your .bash_profile

     from Yunlong He to Everyone:    1:56  PM
     Yunlong, PS1="$ "get rid of my user name. how to get it back?

     from Carl McIntosh to Everyone:    1:56  PM
     Yonlong, open new terminal windo

from Yunlong He to Everyone:    1:57  PM
how to set up .bash_profile?

     from Carl McIntosh to Everyone:    1:58  PM
     echo "PS1='$ '" >> ~/.bash_profile

     from Des to Everyone:    2:00  PM
     PS1='\[\e]0;\w\a\]\n\[\e[32m\]\u@\h \[\e[33m\]\w\[\e[0m\]\n\$ '

     from Carl McIntosh to Everyone:    2:00  PM
     https://www.cyberciti.biz/tips/howto-linux-unix-bash-shell-setup-prompt.html

from Zhilin Yang to Everyone:    2:07  PM
@Des, thanks for the answer! A following question, is there a way that I can add a warning message to 'rm', 
e.g: 'Are you sure you want to delete that file?'  Thanks.

     from Carl McIntosh to Everyone:    2:07  PM
     rm -i

     from Des to Everyone:    2:09  PM
     If you follow https://www.biostarhandbook.com/computer-setup.html 
     it will set up your bash environment correctly (i.e. the command prompt display, and the warnings for rm, cp, etc)

     from Zhilin Yang to Everyone:    2:10  PM
     What about rmdir? There is no '-i' function rt?

     from Sandeep Gurram to Everyone:    2:12  PM
     I think rmdir only removes empty directories. So you only delete an empty directory

from Monika Mehta (internal) to Everyone:    2:11  PM
what do the x v and f do with the tar command?

     Verbal answer:
      x means extract
      v means verbose (list files are they are extracted)
      f indicates the next argument is the name of the tar file to process
      
from Zhilin Yang to Everyone:    2:18  PM
Do you have a microsoft team for this class?

     Verbal answer:
     We are exploring how useful Teams will be... more info in the near future
      
     from Des to Everyone:    2:19  PM
     Q&A forum: https://btep.ccr.cancer.gov/question/biostar/