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Read line1 from file1 - make it line1 of file2

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# 1  
Old 01-18-2013
Read line1 from file1 - make it line1 of file2
Hi friends

I have two files

Code:
cat file1

i am the header
a
b
c
d

Code:
cat file2
e
f
g
h

I want a script that would give me file2 with the header/first line as if in file1

so my final output would be

Code:
cat file2

i am the header
e
f
g
h

# 2  
Old 01-18-2013
Code:
sed '1i'"`sed -n '1p' file1`"'' file2

Use -i (edit in place) if output looks good.
Code:
sed -i '1i'"`sed -n '1p' file1`"'' file2

This User Gave Thanks to Yoda For This Post:
jacobs.smith
# 3  
Old 01-18-2013
With shell:
Code:
{ read;printf '%s\n%s\n' "$REPLY" "$(<file2)";}<file1>file3

Some shells require an argument for read:
Code:
{ read x;printf '%s\n%s\n' "$x" "$(<file2)";}<file1>file3

If I recall correctly, the $(<filename) substitution is not standard,
if your shell doesn't support it, use cat instead.
Last edited by radoulov; 01-18-2013 at 05:01 PM..
This User Gave Thanks to radoulov For This Post:
jacobs.smith
# 4  
Old 01-18-2013
And, if you want to try an awk solution, run
Code:
$ awk 'NR==1 {getline x < "file1"; print x}1' file2

, or,
Code:
$ awk 'NR==1 {getline x < incfile; print x}1' incfile=file1 file2

This User Gave Thanks to RudiC For This Post:
jacobs.smith
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