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--- SED


Replace all files full path with just the filename no directory
$ echo "/home/ubuntu/temp/myfile.txt" | sed 's/.*\///'


Delete all lines that have only white-space
$ sed '/^$/d' input.txt

Delete all non-printable characters
$ echo "Hello$tabWorld" | sed 's/[^[:print:]]//g'

If there is not a match delete the line
$ sed '/agarder/!d' mytext.txt

Deleting a range of lines
$ sed '29,34d' testfile.txt


Deleting lines other than the mentioned
$ sed '29,34!d' testfile.txt

add a blank line after every non-blank line
$ sed G testfile.txt

Search and Replacing a string using sed
$ sed 's/danger/safety/' testfile.txt

Replace a string on a particular line
$  sed '4,9 s/red/blue/' testfile.txt

Running multiple sed commands
$  sed -e 's/red/blue/g' -e 's/sam/bob/' testfile.txt






Making a backup copy before editing a file
$ sed -i.bak -e 's/bob/sammy/g'  testfile.txt

Removing all commented lines & empty lines
$ sed -e 's/#.*//;/^$/d' testfile.txt

Removing all commented lines
$ sed -e 's/#.*//' testfile.txt

insert multiple empty lines in the output, pass multiple G arguments separated by the semi-colon (;) character. 
$ sed 'G;G' textfile.txt


Perform Multiple Substitutions at Once
sed 's/sam/bob/g;s/car/bus/gi' textfile.txt

Replace all uppercase characters of the text with lowercase characters
$ sed  's/\(.*\)/\L\1/' os.txt


Add commas to numbers that have more than 3 digits
$ echo "5098673" | sed -e :a -e 's/\(.*[0-9]\)\([0-9]\{3\}\)/\1,\2/;ta'
 
Replaces tab character with 4 space characters
$ echo -e "1\t2\t3" | sed $'s/\t/    /g'

Replaces 4 consecutive space characters with tab character
$ echo -e "1    2" | sed $'s/    /\t/g'