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reading alternate lines of a file

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# 1  
Old 08-04-2010
Bug reading alternate lines of a file
hi,
i have 2 files.
file1:
Code:
1
2
3
4
5
6

file2:
Code:
a
b
c
d
e
f
g
h
i
j

i want output in file3 as
Code:
1
b
3
d
5
f
h
j

i need a shell script program to this task.please help.
Last edited by Scott; 08-04-2010 at 06:21 AM.. Reason: Code tags
# 2  
Old 08-04-2010
What have you tried so far and what is the "real world problem" of your question?
# 3  
Old 08-04-2010
Hi

Code:
paste -d"\n" file1 file2 | awk '(NR%4==1 || NR%4==0) && $0'

Guru.
This User Gave Thanks to guruprasadpr For This Post:
vidyaj
# 4  
Old 08-04-2010
thanks a lot. before i use to do like this

Code:
$vi f1.sh
paste -d'\n' nice  | while read line2;
do
                echo "$line2"
                read line2
done

$vi f2.sh

paste -d'\n' nice  | while read line2;
do
                echo "$line2"
                read line2
done

$sh newfile.sh >> f1

$sh newfile1.sh >> f2

$vi final.sh
paste -d'\n' f1 f2 | while read line1 && read line2;
do
echo "$line1"
echo "$line2"
done

$sh final.sh
1
a
3
c
5
e
7
g
9
I

your option is brilliant thanks
Last edited by Scott; 08-04-2010 at 06:22 AM.. Reason: Please use code tags
# 5  
Old 08-09-2010
explanation to answer
hello
could you please explain this command?

Code:
awk '(NR%4==1 || NR%4==0) && $0'

Last edited by Scott; 08-09-2010 at 06:22 AM.. Reason: Code tags, please...
# 6  
Old 08-09-2010
Hi
It means: Group the output as 4 lines each, and print the 1st(NR%4==1) and 4th line(NR%4==0) if it is not empty.

Guru.
This User Gave Thanks to guruprasadpr For This Post:
vidyaj
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