Shell Programming and Scripting

I included those ticks around the sed command because I kept getting an error otherwise. But now I recreated the whole scenario/script and tried it again, and everything works as it should.. go figure! At the time, it was driving me nuts because I knew I didn't need them..

Drap!
ksh on AIX. It may just be a bug. Basically, I want to search for lines in file2 that begin with entries in file1 and either edit file2 and save it with the lines removed or write a new file3. Can you suggest another way, like with perl or awk?

Try putting a backslash in front of the ^

hmmm.... now that time I got no change at all. file2 same as file3... I guess I took away the special meaning of the caret so it was literally looking for a ^.

I tried this on the "real" files and file2 has 3457 lines and file1 (ones to be deleted) has 465 lines. When I delete each line, I am expecting to have a file three with 2992 lines in it, but I have 1347 lines...

...long pause to tinker...

The ticks did it! I removed them from the sed command and now file3 is 2992 lines as expected with the output expected (even the 2 liner sample file3 has the right content).

Kudos ya'll! Yahoo...

...okay, one more post for my sanity sake...
it looks like the cmd="$cmd -e /^$WORD/d" line and the sed $cmd... line are redundant can you put what is happening here in newbie english please sir?

This is my attempt:
With each iteration of the while loop the variable WORD is being assigned the "next" value in file1. Therefore, by the end of file1 the cmd variable has all the values in file 1 concatenated into a long string like:

-e /15/d -e /16/d -e /17/d -e /^/d

I understand that, but why did it do the -e /^/d assignment? I thought that was a search qualifyer...

I love this stuff, but it sure can get convoluted.

Thanks for any insight/corrections.

If file1 has a list of numbers like:

15
16
17
18

then after the loop is done looping, $cmd will end up equaling
-e /^15/d -e /^16/d -e /^17/d -e /^18/d

After insertion into the sed command, you end up with

sed -e /^15/d -e /^16/d -e /^17/d -e /^18/d < file2 > file3

The carat symbol is a special symbol.. -e /^/d will delete any line that has a beginning to it.

Unless I missed a requirement to use sed, this is a lot easier with awk:

Code:

awk 'BEGIN{ while ((getline < "file1") > 0) list[$1] = 1 }
!list[$1] { print }' file2 > file3

There are several caveats about your data that are implicit in this solution.