[sed] Multiline trimming

Question

I have a html file that I want to trim. I want to remove a section from the beginning all the way to a given string, and from another string to the end. How do I do that, preferably using sed?

Answer 1

With GNU sed:

sed '/mark1/,/mark2/d;/mark3/,$d'

this

abc
def
mark1
ghi
jkl
mno
mark2
pqr
stu
mark3
vwx
yz

becomes

abc
def
pqr
stu

Answer 2

you can use awk

$ cat file
mark1 dsf
abc
def
before  mark2 after
blah mark1
ghi
jkl
mno
wirds mark2 here
pqr
stu
mark3
vwx
yz

$ awk -vRS="mark2" '/mark1/{gsub("mark1.*","")}/mark3/{ gsub("mark3.*","");print;f=1 } !f ' file

 after
blah
 here
pqr
stu