Find the intersection between two files

Shell Programming and Scripting
1

How can find the intersection between files
for Example:
file1
entry1
entry2
entry3
entry33

file2
entry2
entry4
entry5
.
.
.
.
the output should be
entry2

Thanks in advanced

2

Hi,

You can get the expected output using for loop as follows.

for i in `cat file1 | awk {'print $1'}`
do
grep ${i} file2
done

Thanks,
Aketi...

3

With awk:

awk 'NR==FNR{a[$0]=$0;next}a[$0]' file1 file2

Regards

4

its give me nothing

5

its give me this error

awk: syntax error near line 1
awk: bailing out near line 1

regards,
Ismail

6

Use nawk or /usr/xpg4/bin/awk on Solaris.

7 
grep -f file1 file2
8

hope this one helps for you

awk '{ chk_str="grep ^"$0"$ ./file2_name" ; system(chk_str) }' file1_name

9

Hi.

The command comm finds simple differences and the intersection between the contents of two sorted files. Here is the latter:

% comm -12 file1 file2

Producing:

entry2

See the man page for details ... cheers, drl

10

It is working fine for me.