synth improvement

.aspell.en.pws

@@ -1,4 +1,4 @@
-personal_ws-1.1 en 448 
+personal_ws-1.1 en 451 
 ajax
 apache
 google
@@ -7,6 +7,7 @@ netstat
 multi
 Magnus
 ReqMethod
+httpd
 CDN
 undef
 API
@@ -16,8 +17,8 @@ CET
 github
 delim
 arg
-https
 HTTP's
+https
 VMODs
 Naghibi
 nosni
@@ -52,8 +53,8 @@ RespProtocol
 CType
 SHared
 Henning
-CSS
 DNS
+CSS
 csv
 compressions
 gcc
@@ -96,13 +97,14 @@ subrequests
 HMAC
 strcmp
 README
-httpie
 HTTPie
+httpie
 varnishtop
 urlencoded
 regex
 VaRY
 HLS
+functionalities
 instantiation
 IETF
 maxage
@@ -116,6 +118,7 @@ objectcore
 Makefile
 nlpt
 param
+apachectl
 Blix
 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
 IRC
@@ -127,8 +130,8 @@ cliok
 sudo
 txreq
 RESTful
-IPv
 ipv
+IPv
 Argv
 uint
 Acceptor
@@ -144,8 +147,8 @@ clierr
 LFU
 metadata
 saintmode
-FreeBSD
 freebsd
+FreeBSD
 gunzip
 linux
 Economization
@@ -157,12 +160,12 @@ Aondio
 enmod
 mgt
 releasever
-respstatus
 RespStatus
+respstatus
 vmodtool
 getNonMasqueraded
-HashTwo
 hashtwo
+HashTwo
 tIncluded
 DDoS
 workspace
@@ -176,8 +179,8 @@ SimpleHTTPServer
 Kamp
 codename
 LRU
-ReqURL
 ReqUrl
+ReqURL
 asts
 SELinux
 LTS
@@ -261,19 +264,19 @@ helloworldtest
 varnishapi
 ubuntu
 Footbar
-rst
 VBE
+rst
 VCA
-src
 vcc
+src
 recv
 subrequest
 util
 SQL
 VDD
 VBP
-vcl
 VAV
+vcl
 VXIDs
 TLS
 setsebool
@@ -297,8 +300,8 @@ requesters
 Rub�n
 Webdev
 systemctl
-VIN
 JPEG
+VIN
 ttl
 rxreq
 rxres
@@ -311,8 +314,8 @@ url
 testbed
 hdrbytes
 Arianna
-VLU
 utf
+VLU
 BereqURL
 malloc
 dotMobi's
@@ -424,6 +427,7 @@ xb
 VM
 Hagander
 ETags
+CentOS
 ws
 TOUPDATE
 Fialka
@@ -433,8 +437,8 @@ localhost
 vstatdprobe
 Karstensen
 varnishlog
-ETag
 Etag
+ETag
 substring
 noverify
 AUTOEXTEND

varnish_book.rst

@@ -4447,9 +4447,11 @@ VCL – ``vcl_deliver``
 VCL – ``vcl_synth``
 -------------------
 
-- Used to generate content from within Varnish, without talking to the backend
-- Error messages go here by default
-- Other use cases: Redirecting users (301/302 redirects)
+- Used to generate content within Varnish
+- Error messages can be created here
+- Other use cases: redirecting users (301/302 redirects)
+
+**vcl/default-vcl_synth.vcl**:
 
 .. include:: vcl/default-vcl_synth.vcl
    :literal:
@@ -4458,22 +4460,23 @@ VCL – ``vcl_synth``
 
 .. container:: handout
 
-   To make a distinction between VCL synthetic responses and internally generated errors (when trying to fetch an object), there are two subroutines that handle errors in Varnish.
-   One is ``vcl_synth``, and the other is ``vcl_backend_error``.
-   To return control to ``vcl_synth``,call the ``synth()`` function like this::
+   You can create synthetic responses, e.g., personalized error messages, in ``vcl_synth``.
+   To call this subroutine you do::
 
      return (synth(status_code, "reason"));
 
-   Note that the syntax ``synth`` is not a keyword, but a function with arguments.
+   Note that ``synth`` is not a keyword, but a function with arguments.
 
    You must explicitly return the ``status code`` and ``reason`` arguments for ``vcl_synth``.
    Setting headers on synthetic response bodies are done on ``resp.http``.
 
    .. note::
-      Note how you can use ``{"`` and ``"}`` to make multi-line strings. 
-      This is not limited to the ``synthetic()`` function, but can be used anywhere.
+
+      From ``vcl/default-vcl_synth.vcl``, note that ``{"`` and ``"}`` can be used to make multi-line strings. 
+      This is not limited to the ``synthetic()`` function, but one can be used anywhere.
 
    .. note::
+
       A ``vcl_synth`` defined object is never stored in cache, contrary to a ``vcl_backend_error`` defined object, which may end up in cache.
       ``vcl_synth`` and ``vcl_backend_error`` replace ``vcl_error`` from Varnish 3.