Extracting multiple lines of data between two delimiters

Question

I have a log file containing multiple lines of data. I need to extract and the all the lines between the delimiters and save it to the output file

input.log

Some data 
<delim_begin>ABC<delim_end>
some data
<delim_begin>DEF<delim_end>
some data

The output.log file should look like

ABC

DEF

I tried this code but it does not work, it prints all the content of input.log

sed 's/<delim_begin>\(.*\)<delim_end>/\1/g' input.log > output.log

score 4 · Accepted Answer · answered Mar 08 '16 at 20:53

4

Using awk you can do it using custom field separator:

awk -F '<(delim_begin|delim_end)>' 'NF>2{print $2}' file
ABC
DEF

Using grep -P (PCRE):

grep -oP '(?<=<delim_begin>).*(?=<delim_end>)' file
ABC
DEF

answered Mar 08 '16 at 20:53

anubhava

I tried both the methods but all I get is empty output.log file – msd_2 Mar 08 '16 at 21:02

score 0 · Answer 2 · answered Mar 08 '16 at 21:06

0

sed alternative

$ sed -nr 's/<delim_begin>(.*)<delim_end>/\1/p' file

ABC
DEF

answered Mar 08 '16 at 21:06

karakfa

score 0 · Answer 3 · edited Mar 08 '16 at 21:17

0

This should do it:

cat file | awk -F '<(delim_begin|delim_end)>' '{print $2}'

edited Mar 08 '16 at 21:17

jkdba

answered Mar 08 '16 at 21:08

Dheeraj R

[Useless use of `cat`](http://stackoverflow.com/q/11710552/660921) ;-) Just using `awk -F ... file` also works ;-) – Martin Tournoij Mar 09 '16 at 01:51

score 0 · Answer 4 · answered Mar 09 '16 at 13:05

0

You can use this command -

cat file | grep "<delim_begin>.*<delim_end>" | sed 's/<delim_begin>//g' | sed 's/<delim_end>//' > output.log

answered Mar 09 '16 at 13:05

avivb

4 Answers4