In OS X, there is a command-line utility called security which is designed to access the Keychain. It can return the password of an entry in the Keychain, which is what I'm trying to do. When I run security find-internet-password -ga an_entry | grep "password" I get the following output, as expected:
password: "apassword123"
I would like to extract the text between the quotes. grep, specifically pcregrep, should work but doesn't:
echo 'password: "apassword123"' | pcregrep -o '^password:\s"(?!_)\K[^"]+'
Returns:
apassword123
As expected, but:
security find-internet-password -ga anentry | pcregrep -o '^password:\s"(?!_)\K[^"]+'
Returns:
password: "apassword123"
Which is absurd.
Your output actually doesn't get through the grep as it's on stderr. You should be able to do this by redirecting the stderr to stdout like
security find-internet-password -ga anentry 2>&1 | pcregrep -o '^password:\s"(?!_)\K[^"]+'