Thank you for this report. The example appears to be correct.
The -c is an OPTIONAL command line parameter for the digest_pw_auth helper. Which is documented in the helper manual. (online as: http://www.squid-cache.org/Versions/v3/3.2/manuals/digest_file_auth.html)
The -c is NOT part of the syntax for auth_param directive which is being documented in squid.conf.documentated
Amos Jeffries Squid Project -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org