linux - extracting two ranges of lines of a file a and putting them as a data block with shell commands -


i have 2 blocks of data in file, foo.txt following:

a 1 b 2 c 3     d 4     e 5 f 6 g 7 h 8 9

i'd extract rows 2:4 , 6:8 , put them following:

b 2 f 6 c 3 g 7 d 4 h 8

i try using auxiliary files:

sed -n '2,4p' foo.txt > tmp1; sed -n '6,8p' foo.txt > tmp2; paste tmp1 tmp2 > output; rm tmp1 tmp2

but there better way without auxiliary files? thanks!

using process substitution:

$ paste <(sed -n '2,4p' foo.txt) <(sed -n '6,8p' foo.txt) > output $ cat output  b 2 f 6 c 3 g 7 d 4 h 8 $

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