Regex matching using SED in bash

Question

I want to match the following line with the regex in sed:

db=connect_str=DBI:SQLAnywhere:ENG=ABC1_hostname12;DBN=ABC12;UID=USERID;PWD=passwd123;LINKS=tcpip{host=10.11.12.13:1234}

The regex I am using is:

sed -n '/ABC1_.+;/p' Config/db_conn.cfg

but this does not work. On the other hand, it works if I use:

sed -n '/ABC1_.*;/p' Config/db_conn.cfg

Can someone please explain why it's not working? Also is there another way to match it?

Answer 1

It's because sed is basic regex by default, which needs + to be escaped or else it represents a literal + instead of a regex +:

sed -n '/ABC1_.\+;/p' Config/db_conn.cfg

To use regex you're familiar with try sed -r -n (extended regex) and then you can do:

sed -r -n '/ABC1_.+;/p' Config/db_conn.cfg