The given `sed` command extracts and prints a specific substring...

The given sed command extracts and prints a specific substring that matches a pattern from the input. Here's a detailed breakdown of the code:

Code Explanation:

1. sed -nE:

   • sed: Stream editor, used to parse and transform text.
   • -n: Suppresses automatic printing of input lines. This means sed will only print the lines explicitly instructed to via the p command.
   • -E: Enables extended regular expressions, making it easier to write complex patterns (instead of escaping special characters like ( and )).

2. 's/.*"(.*OSX-[^"]*)".*/\1/p':

   • s/.../.../: This is the substitute command, used to search for a pattern and replace it.
   • .*: Matches any text (0 or more characters).
   • "(.*OSX-[^"]*)":
     • ": Matches a literal double-quote.
     • (.*OSX-[^"]*): Captures a group (\1), where:
       • .*: Matches any text before the substring OSX-.
       • OSX-: Matches the literal string OSX-.
       • [^"]*: Matches 0 or more characters that are not a double-quote.
     • This pattern effectively captures any substring starting with OSX- and continuing until the next double-quote.
   • .*: Matches everything after the last double-quote.
   • \1: Refers to the captured group (contents within ( ... )), which contains the desired substring starting with OSX-.
   • p: Prints the result of the substitution (the captured group).

What the Code Does:

This sed command extracts and prints the portion of a line that:

• Is enclosed in double-quotes (") and
• Contains a substring starting with OSX-.

If no such match is found, the line is ignored (due to -n and no p without a match).

Example Input and Output:

Input Line:

Some text "random stuff OSX-12345-abc more text" other text

Output:

OSX-12345-abc

This happens because the substring "OSX-12345-abc" is matched, and the OSX-12345-abc part is extracted and printed.