Using Diff to compare 2 arrays

Shell Programming and Scripting
1

I have two arrays and they look like this:

 array=(`cat /local/mnt/*sys/*includes|grep -v NEW`) 

array2=(`cat /tmp/*sys.z |grep -v NEW`)

I am trying to compare them but I need to use the diff -u command. I am not sure how to do this. I cannot just do

 diff  -u ${array[@]} ${array2[@]}

I cannot do "for i in" as there are two arrays. I did not want to use the test format, but the diff -u command. Any suggestions?

2

You use diff on files, not strings.

You can try this:

diff <(cat /local/mnt/*sys/*includes|grep -v NEW) <(cat /tmp/*sys.z |grep -v NEW)
3

when I run that command that Corona suggested, I get "diff: 2 filename arguments required" as I do with every attempt to use diff for these filelists.

4

It certainly doesn't do that for me. Can you show me exactly what you're doing, word for word, letter for letter, keystroke for keystroke? And what shell you're using?

5

Your last question, where you mention please let me know "letter by letter" how you typed the command made me think that my typing was bad. I found that the second cat statement did not have a space. Putting a space made it work.

)   <(cat /tmp/

instead of

) <(cat /tmp/
1 Like