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Re: curl-config oddity

From: Michael Wallner <>
Date: Thu, 10 May 2007 18:56:54 +0200

Hi Dan, thanks for your answer!

Dan Fandrich wrote:
> Michael Wallner wrote:
>> I just recognized that my SSL library detection magic in configure
>> does not work anymore and now I wonder why curl-config (in CVS only?)
>> behaves as follows:
> Are you basing your opinion that the SSL library detection doesn't work
> on the output of curl-config or do you have other data?

Well, it's about my app's SSL library detection :) I need to know which
SSL library is used by libcurl to set the right crypto locking callbacks.
I used to test for the linker flags in my configure to determine the SSL
library used by libcurl.

>> As you can see, it lists SSL as feature but not the required linker flags...
>> Any idea where to start looking at?
> This is deliberate--your system is one that loads dependencies recursively
> from the libraries (e.g. ELF supports this), so there's no need to make a
> dependency on OpenSSL (for example) in the application if it's
> not explicitly calling OpenSSL functions (in the latter case, the app must
> manually add the proper -l option to the link command-line). Doing it this
> way allows an app to run with a libcurl that uses OpenSSL, GnuTLS, yassl, NSS
> or any other SSL library supported in the future without recompiling.

The distributions (Kubuntu) curl-config gives me the following:
mike_at_honeybadger:~/cvs/curl$ /usr/bin/curl-config --libs
-L/usr/lib -lcurl -L/usr/lib -lgssapi_krb5 -lkrb5 -lk5crypto -lcom_err -lkrb5support -lresolv -lidn -lssl -lcrypto -ldl -lssl -lcrypto -lz

mike_at_honeybadger:~/cvs/curl$ /usr/bin/curl-config --feature

mike_at_honeybadger:~/cvs/curl$ /usr/bin/curl-config --version
libcurl 7.15.5

So I wonder if I'm doing something wrong or I'm just missing some
curl configure flags, or do you think this flags are added by the
distributions libcurl package maintainer?


Received on 2007-05-10