- VxWorks dll
- Posted by Praveen on November 24th, 2003
Hi
can anybody throw some light on the differences between dll in
vxworks and shared objects in LInux?? Also please tell me wether
moduleLoad and moduleUnload do the same thing that dlopen and dlclose
do in Linux..
Thanx in advance,
Praveen M Nair.
- Posted by CBFalconer on November 24th, 2003
Praveen wrote:
Why not think about fundamentals? Conceive of a machine with two
(or more) programs simultaneously loaded, each having it's own
data areas, stack, etc. These can be executed by a single CPU by
interrupting at suitable times and changing register contents, and
give the appearance of simultaneous operation. Now arrange that
machine to minimize the number of registers required to specify
data areas, program areas, etc. Add a new process that never
really runs, but holds binary code. That code can be called from
either of the other processes as needed. It may even need some
private data area, although that would not be a wise arrangement.
We can call something dlopen and use it to mount that common code
in the system, to do any needed initialization, and to record
where it is located in some suitable manner. We can call
something moduleUnload to remove it all when done.
is illusion.
--
Chuck F (cbfalconer@yahoo.com) (cbfalconer@worldnet.att.net)
Available for consulting/temporary embedded and systems.
<http://cbfalconer.home.att.net> USE worldnet address!
- Posted by Praveen on November 25th, 2003
CBFalconer <cbfalconer@yahoo.com> wrote in message news:<3FC27245.EF7E204E@yahoo.com>...
Thanx.. but i have heard that dll's in VxWorks can be executables
also, is it true?? if so how do i know from the code?? is it that it
will contain a main similar to my executables in Linux??
-Praveen M Nair.
- Posted by Pascal CORBILLON on November 25th, 2003
"Praveen" <praveen.nair@patni.com> a écrit dans le message news:
6352d824.0311250334.509a97a1@posting.google.com...
DLL: dynamic link library. Object file that will be opened by an
application and used in order to service it.
VxWorks uses the principle of modules which are object files
obtained after the compilation process.
Executable file: object file where all addresses are fixed and all
missing symbols are resolved.
The other type is relocatable files: the code start address is let to 0
and the external references (eg printf()) are unresolved. The only
way to execute the code is to link the relocatable file (statically
or dynamically).
main is just a hook. In VxWorks, the entry point for a task is
whatever the user want...
Pascal