Confused: Which headers are "The Headers"?

Couling · 06-14-2010, 12:51 PM

Hi All

A little background:
I've been a programmer for a while; on windows mostly but I'm starting to learn all that I can about linux software.

To help me with this I've picked up a funky little NAS which has ssh access to its (i believe uLinux) environment. I've also managed to find a compiler for it (gcc compiled for ARM - GNU/Linux).

The plot thickens
I've had some headaches but I've now managed to compile Apache2 without DSO support... so far so good.

In getting this far I've been told by a number of people i will need "the headers" specific to the device (the NAS didn't come with source code).

Since Apache 2 (without DSO) compiled fine I know i definitely have some headers. But DSO won't build with errors that lead me to believe it may be a header issue.

The question:
So i have some headers which educated guess work suggests to me that these are the headers for the std c/c++ libraries.

It would help me greatly in finding "the headers" to know what they are the headers for. Any suggestions on which headers would have come with the compiler i downloaded.

Sorry if this is a silly question without a meaningful answer, but if this is the case any clarification would be greatly appreciated.

Thanks.

AlucardZero · 06-14-2010, 02:17 PM

We don't really have enough information to tell you. It would help if you posted the errors you are getting!

Couling · 06-14-2010, 05:01 PM

In this particular case the error is as follows.

Code:

../httpd-2.2.15/configure
<...snip>

Checking for DSO...
checking for dlopen... no
checking for dlopen in -ldl... no
checking for load_image in -lroot... no
configure: error: Could not detect suitable DSO implementation
configure failed for srclib/apr

This says to me that either my system does not support DSO (another avenue I can look into), or I'm missing the headers for the support that it does have.

AlucardZero · 06-14-2010, 05:59 PM

Looks like DSO is in APR, so.. install APR, or try the --with-included-apr configure flag

Couling · 06-15-2010, 01:29 PM

Quote:

Originally Posted by AlucardZero

Looks like DSO is in APR, so.. install APR, or try the --with-included-apr configure flag

No. APR provides a wrapper for DSO, it doesnt seem to provide DSO itself (DSO in APR API).
Reading into what DSO is (DSO in Apache 2.2 Documentation), I doubt it's a part of apache at all, but something provided by the OS.
Most likely this will be something provided by the kernel as it gives support for dynamically loading share object (.so) files.

My question re-worded
Since asking this question I've cleared up a lot of my confusion.
It would be better to state my question as:

I have a linux box that came without source code and I wish to set up a build environment for it.

I know that I will need:
Standard c/c++ headers.
Kernel headers (is it possible to find out what modules are in my kernel???)
Headers for libraries in my /lib /usr/lib /opt/lib directories.

Is there anything else I will need to get?