awk - Shell Script - can't find string in file using grep -

i've come across weird problem can't solve myself. i've got 2 files, content follows:

file1.txt

butterscotch;lkt+4s7yhzf/g sox;wrwmzn6hd table;k4ypik+sfftfs tram;yay3opp9ie number;e/wwif5aihuy buttler;nsadlkt+4s7yhz wzahwahwah;pyay3opp9ieh

file2.txt

butterscotch;lkt+4s7yhzf/g sox;wrwmzn6hd table;k4ypik+sfftfs tram;yay3opp9ie number;e/wwif5aihuy

i need find differences between 2 files entries before semicolon, first utilize awk entries:

awk 'begin {fs=";"}; {print $1}' file1.txt > output1.txt awk 'begin {fs=";"}; {print $1}' file2.txt > output2.txt

new files contain entries follows:

output1.txt

butterscotch sox table tram number buttler wzahwahwah

output2.txt

butterscotch sox table tram number

then utilize grep -fxvf output2.txt output1.txt > diff.txt print out differences between output2.txt , output1.txt file looks this:

diff.txt

buttler wzahwahwah

now tricky part. need find , print out file whole lines file1.txt start entries diff.txt. i'm declaring variable , this:

variable=$(cat diff.txt) grep $variable output1.txt > delete.txt

so illustration should this:

delete.txt

buttler;nsadlkt+4s7yhz wzahwahwah;pyay3opp9ieh

but unfortunately error:

grep: wzahwahwah: no such file or directory

file delete.txt instead of desired info contains:

/home/working/file1.txt:buttler;nsadlkt+4s7yhz

so it's far need get. i've noticed when remove file1.txt

wzahwahwah;pyay3opp9ieh

i no errors , desired file looks like:

buttler;nsadlkt+4s7yhz

any ideas why isn't working?

instead of cat , subsequent grep utilize grep:

grep -ff diff.txt file1.txt buttler;nsadlkt+4s7yhz wzahwahwah;pyay3opp9ieh

shell awk grep

Jaimee