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Sed | awk to delete a line after matching the next line

if it Name

goes back and then removes the name

Name john
Age 30

Name Alice

Name Travis
Age 12

Name Monty

Name Hannah

desired output

Name john
Age 30

Name Travis
Age 12

Name Hannah

The commands I've tried:

sed '/^Name/ {N; /\n$/d}' file.txt

sed '/Name/{$!N;/\n\nName/!P;D}' file.txt
+3


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3 answers


Here's a method using awk

,

awk_script:

BEGIN{a=0}                                                                                                                                                                                                   
/Name/{ if(a==1){print $0;name=""}else{name=$0"\n"} a=1 }
/Age/{printf "%s%s\n\n",name,$0; a=0;}

Then run:



$ awk -f awk_sc file.txt
Name john
Age 30

Name Travis
Age 12

Name Hannah

Brief explanation:

Variable a

is the flag used for recording if previously shown Name

. Set a=0

after printing lines

+1


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You can use this awk command:



awk 'NF && /^Name/ {n=NR; p=$0; next}
     NF && n {if ($0 !~ /^Name/) print p; n=0} END{if (n) print p} 1' file

Name john
Age 30


Name Travis
Age 12


Name Hannah
+1


source


It may not be exactly what you are looking for, but why not try to keep only what interests you.

 sed -n '/^Name/ {N; /Age.*/p}' file.txt

You will get the following result

Name john
Age 30
Name Travis
Age 12
0


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