Shell Programming and Scripting

Hi,

I have a single-column file1 having records like:

00AB01/11
43TG22/00
78RC09/34
......
......

and a second file , file 2 having two columns like

78RC09/34 1
45FD11/11 2
00AB01/11 3
43TG22/00 4
......
......


and i would like to compare the first column of file1 with the first column of file2 and get the desired output in a third file (i.e. file3) as follows:

00AB01/11 2
43TG22/00 4
78RC09/34 1
......
......


so i want to get the records from file2 that have the same $1 with file1

i've already tried doing the following in awk:

Code:

awk 'FILENAME=="file1"{a[$1]=$1}FILENAME=="file2"{if(a[$1]==$1){print;}}' file1 file2 > file3

and i'm getting an empty file...probably the comparison is not done...

any suggestions??

thanks in advance!

Code:

grep -f file1 file2 > file3

--ahamed

thanks ahamed, unfortunately, i've tried it and it doesn't work.

In what way does it "not work"?

What's your system?

it does not produce any output...just for the record, i'm on ubuntu

Code:

~/unix.com$ awk 'NR==FNR{A[$1]=$2;next}$0=$1 OFS A[$1]' file2 file1

thank you tukuyomi, however the code you gave me produces only the the first column of file2 and does not go through the comparison...

just to inform that file1 has 2000 unique records and file2 has 5000 unique records... therefore i would expect to get as a result after the comparison in file3 exactly 2000 records.... based on your code i get a file that has 5000 records (therefore it didn't go through the comparison of file1 vs. file2)