Add a simple SMTP example program, patterned after some of the existing
examples, and the curl application.
This version addresses issues raised by David Woodhouse on comments in
the simplesmtp.c example.
This script is the start of a helper tool that scans a source code and
outputs the most recent libcurl version it finds symbols for. Meaning
that if there's no conditions in the code, that's the earliest libcurl
version the scanned code requires.
It is not added to the Makefile.am yet as it is still a bit crude, but
I'm committing it to keep it and allow us to work on it.
This is a meta symbol. OR this value together with a single specific
auth value to force libcurl to probe for un-restricted auth and if not,
only that single auth algorithm is acceptable.
For example you can use CURLAUTH_DIGEST|CURLAUTH_ONLY to make libcurl
first probe for what method to use, but yet only consider Digest to be
acceptable.
Using _only_ CURLAUTH_DIGEST without the CURLAUTH_ONLY field, will make
libcurl explicitly use Digest right away and not do any probing.
An example application source code sending SMTP mail with the multi
interface. It is based on the code Alona Rossen provided, which in turn
is based on existing example/test code, and I converted it even more
into a decent example with a fair multi API use, put the info required
to edit at the top and I added some comments.
I've developed a script I call symbol-scan.pl that scans the curl.h and
multi.h header files and compare the symbols it finds in there with the
symbols symbols-in-versions documents and outputs a report on the
differences. Using this I've dug through the history to fill up
symbols-in-versions with all the symbols my script found mismatches for.
I will commit symbol-scan.pl separatly and think of a way to put it to
use in the build/tests so that we from now on will get this in-sync
check automatically.
The invocation of autoconf's AC_PATH_PROG( ) is not quite right for
finding curl-config. This fix corrects the negative case (where
curl-config is not found).
