sed examples Text manupulation using the sed

SED is very powerful command in context of text manupulation

sed 's/string1/string2/g' ------ Replace string1 with string2

sed 's/\(.*\)1/\12/g' ---------------Modify anystring1 to anystring2

sed '/ *#/d; /^ *$/d' ---------Remove comments and blank lines

sed ':a; /\\$/N; s/\\\n//; ta' ----------- Concatenate lines with trailing \

sed 's/[ \t]*$//' ----------Remove trailing spaces from lines

sed 's/\([\\`\\"$\\\\]\)/\\\1/g' --Escape shell meta characters active within double quotes

seq 10 | sed "s/^/ /; s/ *\(.\{7,\}\)/\1/" ---------Right align numbers

sed -n '1000p;1000q' ----------Print 1000th line

sed -n '10,20p;20q' -----------Print lines 10 to 20

sed -n 's/.*<\/title>.*/\1/ip;T;q' ------------Extract title from HTML web page

sed -i 42d ~/.ssh/known_hosts ---------------Delete a particular line