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Hi Gurus,
I have a text file with many lines in it. I would like just to concatenate the first 2 lines and the remaining lines as it is into a new file.
Input file:
abcdef
stuvw
pqrst
xyz
output:
abcdefstuvw
pqrst
xyz
I am able to do it with looping throigh the lines and printing on to the new file. Is it possible to get a sed or perl command to do it?
printf '%s\n' '1,2j' 'w newfile.txt' | ed -s infile.txt
The 'j' command joins lines together. The 'w' command writes the changes to a file. Used alone it writes back to the original, or with an argument you can create a new file.
Use '%p' to print the modifications to stdout.
Note also that if you need a space or something between the merged lines you'll need to add another command to insert it first.
Maybe I shouldn't have used the word "instead". Either way will work just fine.
I like ed because it's light, the expressions needed in this case are clearer and more intuitive, and you can write out directly to a file, even back to the original. Of course you do need to use a pipe or similar to feed the commands to ed through stdin, so perhaps it's a wash.
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