通过使用sed wit regexp进行替换

Question

Need to replace string in a file with regular expression. My regexp is api.(dev[0-9]+\\.)?side.com and I am using it with call:

sed "s/api.(dev[0-9]+\.)?side.com/$SERVER_HOST_VALUE/g"

But it didn't found any strings like "api.side.com" or "api.dev02.side.com". Regular expression worked for me and not worked only with "sed" command.

So how to use current regexp properly with sed ?

Answer 1

Based on @fedorqui's and @hwnd's recommendation, use the -r option :

sed -re "s/api.(dev[0-9]+\.)?side.com/$SERVER_HOST_VALUE/g"

Note: If you use single quotes instead of double quotes, the variable $SERVER_HOST_VALUE won't be expanded.

Test

SERVER_HOST_VALUE="AWESOME"
tests=( "api.side.com" "api.dev05.side.com" )
for t in "${tests[@]}"; do 
    echo "$t" | sed -re "s/api.(dev[0-9]+\.)?side.com/$SERVER_HOST_VALUE/g"
done

Output

Note how the matches are replaced by $SERVER_HOST_VALUE :

AWESOME
AWESOME