[SOLVED] Sed remove between patterns

pedropt · 11-19-2019, 08:20 AM

This code is probably here already in the forum , but search engine did not poped up any results for what i need .

And what i need is pretty simple , use sed to remove everything between 2 patterns , but do not remove the patterns .

Example :

#starthere
dwfwef
efewf
wefewf
#endhere

Desired output

#starthere
#endhere

This next code removes also the patterns , but i dont want them to be removed , i want only what there is between them .

Code:

sed -i "/\#starthere/,/\#endhere/d" myfile

grail · 11-19-2019, 08:30 AM

http://www.grymoire.com/Unix/Sed.html

After the dozens of questions you have asked on Sed, you should have the above well book marked and be able to solve this

scasey · 11-19-2019, 08:34 AM

By default, sed works on one line at a time.
There are patterns that will check multiple lines.

Given your example, it appears that you want to delete all lines that don't match #starthere or #endhere. Yes?
Think of the problem that way.

And, again, please use code tags when posting code or output. See the link in my signature.

teckk · 11-19-2019, 08:45 AM

Code:

list="
#starthere
dwfwef
efewf
wefewf
#endhere
"

sed -n '/^#/p' <<< "$list"
#starthere
#endhere

pan64 · 11-19-2019, 08:51 AM

or you might want to print that two lines explicitly

pedropt · 11-19-2019, 08:58 AM

Grail , you are right , but i dont take notes for some codes or sometimes i forget to mention in code what that instruction does , then i get lost .

teckk , nope .

i only want to delete the lines between those 2 patterns , everything before and after those patterns should not be touched .

example :

Quote:

something
addfdf
dsfrre
#starthere
trjhtr
qweorqro
#endhere
4677ret
124253
fgrtrjuruj

Desired output :

Quote:

something
addfdf
dsfrre
#starthere
#endhere
4677ret
124253
fgrtrjuruj

with :

Quote:

sed -n '/\#starthere/,/\#endhere/p' file

i am almost there , but if i change the p to d then will delete everything

crts · 11-19-2019, 09:41 AM

Code:

sed '/\#starthere/,/\#endhere/{d}' file

You can group more than one command between {}. They will only be executed when you are between the matched region. Use this to match the lines you want to preserve. There have already been good suggestions on how to preserve them. You can match each one explicitly or both with a RegEx, you can preserve them by explicitly printing or by jumping to the end via 'b' command.

danielbmartin · 11-19-2019, 09:43 AM

With this InFile ...

Code:

apple
banana
cherry
starthere
dwfwef
efewf
wefewf
endhere
peach
pear
pineapple

... this sed ...

Code:

sed '/^starthere/,/^endhere/{//!d;};' $InFile >$OutFile

... produced this OutFile ...

Code:

apple
banana
cherry
starthere
endhere
peach
pear
pineapple

I didn't write this, credit to author SLePort. I found it at:
https://stackoverflow.com/questions/...ching-patterns

Daniel B. Martin

.

pedropt · 11-19-2019, 09:54 AM

Thank Daniel , it works perfectly