$ curl --version
curl 7.52.1 (i686-pc-linux-gnu) libcurl/7.52.1 OpenSSL/1.0.2s zlib/1.2.8 libidn2/0.16 libpsl/0.17.0 (+libidn2/0.16) libssh2/1.7.0 nghttp2/1.18.1 librtmp/2.3
Protocols: dict file ftp ftps gopher http https imap imaps ldap ldaps pop3 pop3s rtmp rtsp scp sftp smb smbs smtp smtps telnet tftp 
Features: AsynchDNS IDN IPv6 Largefile GSS-API Kerberos SPNEGO NTLM NTLM_WB SSL libz TLS-SRP HTTP2 UnixSockets HTTPS-proxy PSL 

$ curl -4 -v --proxy http://elite:3128/ --anyauth --fail 'http://unittest:password@cam-unittest-fixture.brightsign/~unittest/cgi-bin/auth-digest/make-large2.rb?maxage=0&bytes=3'
*   Trying 172.30.1.1...
* TCP_NODELAY set
* Connected to (nil) (172.30.1.1) port 3128 (#0)
> GET http://unittest:password@cam-unittest-fixture.brightsign/~unittest/cgi-bin/auth-digest/make-large2.rb?maxage=0&bytes=310 HTTP/1.1
> Host: cam-unittest-fixture.brightsign
> User-Agent: curl/7.52.1
> Accept: */*
> Proxy-Connection: Keep-Alive
> 
< HTTP/1.1 401 Unauthorized
< Date: Sat, 03 Aug 2019 20:25:13 GMT
< Server: Apache/2.4.25 (Debian)
< WWW-Authenticate: Digest realm="Unit test realm", nonce="daWsRTyPBQA=af0f54dd56ec977de84277e3bdea682d83f4971f", algorithm=MD5, qop="auth"
< Content-Length: 478
< Content-Type: text/html; charset=iso-8859-1
< X-Cache: MISS from elite
< X-Cache-Lookup: HIT from elite:3128
< Via: 1.1 elite (squid/3.5.23)
< Connection: keep-alive
< 
* Ignoring the response-body
* Curl_http_done: called premature == 0
* Connection #0 to host (nil) left intact
* Issue another request to this URL: 'http://unittest:password@cam-unittest-fixture.brightsign/~unittest/cgi-bin/auth-digest/make-large2.rb?maxage=0&bytes=310'
* Found bundle for host cam-unittest-fixture.brightsign: 0x574fee98 [can pipeline]
* Re-using existing connection! (#0) with proxy (nil)
* Connected to (nil) (172.30.1.1) port 3128 (#0)
* Server auth using Digest with user 'unittest'
> GET http://unittest:password@cam-unittest-fixture.brightsign/~unittest/cgi-bin/auth-digest/make-large2.rb?maxage=0&bytes=310 HTTP/1.1
> Host: cam-unittest-fixture.brightsign
> Authorization: Digest username="unittest", realm="Unit test realm", nonce="daWsRTyPBQA=af0f54dd56ec977de84277e3bdea682d83f4971f", uri="/~unittest/cgi-bin/auth-digest/make-large2.rb?maxage=0&bytes=310", cnonce="YWFiZmUwMGM5NGRjODE4ODcwMmQyZDJmNmJjNWEyMWU=", nc=00000001, qop=auth, response="eadd69ed87b6033cc97699175ebff64e", algorithm="MD5"
> User-Agent: curl/7.52.1
> Accept: */*
> Proxy-Connection: Keep-Alive
> 
< HTTP/1.1 200 OK
< Date: Sat, 03 Aug 2019 20:25:13 GMT
< Server: Apache/2.4.25 (Debian)
< Accept-Ranges: bytes
< Cache-Control: no-cache
< Rendered: 2019-08-03 21:25:13 +0100
< Authentication-Info: rspauth="df0cfcfc7e3314e60cf31bca453fe078", cnonce="YWFiZmUwMGM5NGRjODE4ODcwMmQyZDJmNmJjNWEyMWU=", nc=00000001, qop=auth
< Content-Length: 310
< Content-Type: text/test
< X-Cache: MISS from elite
< X-Cache-Lookup: HIT from elite:3128
< Via: 1.1 elite (squid/3.5.23)
< Connection: keep-alive
< 
* Curl_http_done: called premature == 0
* Connection #0 to host (nil) left intact
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