Explicitly require pkg-config. It's not installed by default on OS X

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Makefile

@@ -10,6 +10,11 @@ else
 OPT_FLAGS := -O2 -g -Wall
 endif
 
+PKGCONFIG=$(shell pkg-config --version)
+ifeq ($(PKGCONFIG),)
+$(error "No pkg-config. Cannot continue");
+endif
+
 # Allow people to override OpenSSL and build it statically, if they need
 # a special build for the DTLS support. $(OPENSSL) points to the build 
 # dir; there's no need to install it anywhere (we link it statically).

openconnect.html

@@ -45,7 +45,8 @@ <H2>Getting started</H2>
       Some distributions like Fedora have packages; otherwise you can
       download it and type '<TT>make</TT>' to build it. To build it,
       you'll want development packages for <TT>libxml2</TT>, <TT>zlib</TT>
-      and obviously <TT>OpenSSL</TT> to be installed.
+      and obviously <TT>OpenSSL</TT> to be installed. You will also need
+      <tt>pkg-config</tt>.
   </LI>
   <LI>Install a <TT>vpnc-script</TT>.<BR>
       This script is what sets up all the addresses and routes for you; it's the
@@ -182,6 +183,7 @@ <H2>Release Notes / Changelog</H2>
 <UL>
   <LI><B>OpenConnect HEAD</B><BR>
      <UL>
+       <LI>Be more explicit about requiring <TT>pkg-config</TT>.</LI>
        <LI>Invoke script with <tt>reason=reconnect</tt> on CSTP reconnect.</LI>
        <LI>Add <TT>--non-inter</TT> option to avoid all user input.</LI>
      </UL><BR>
@@ -390,6 +392,7 @@ <H2>ConnMan support</H2>
 <H2>Requirements</H2>
 The basic text-mode client uses the following libraries:
 <UL>
+  <LI><B>pkg-config</B></LI>
   <LI><B>OpenSSL</B> &mdash; ideally at least 0.9.8m, although all versions from 0.9.7 onwards will work for basic connectivity. See note on DTLS compatibility below.</LI>
   <LI><B>libxml2</B></LI>
   <LI><B>zlib</B></LI>
@@ -476,6 +479,6 @@ <H3>FreeBSD</H3>
 <hr>
 <address>David Woodhouse &lt;<A HREF="mailto:dwmw2@infradead.org">dwmw2@infradead.org</A>&gt;</address>
 <!-- hhmts start -->
-Last modified: Sun May 29 09:23:23 BST 2011
+Last modified: Sun May 29 09:24:58 BST 2011
 <!-- hhmts end -->
 </body> </html>