PORTS Forum

Ports and Interfaces => USB => Topic started by: Martin on July 26, 2014, 10:12:50 pm

Title: libusb and Eclipse noob question.
Post by: Martin on July 26, 2014, 10:12:50 pm
Hi All.

I'm still learning how to do things in a  Linux environment, and I want to compile the generic_hid example using Eclipse. I can do this without issue from the command line, but I cant figure out how to pass the -lusb-1.0 option to Eclipse.

On the command line I use:
gcc -o ghid generic_hid.c -I/usr/include/libusb-1.0/ -lusb-1.0
which works fine.

Can anyone help out with this?  I noticed a search on this site using eclipse as a key work did not reveal much. Is anyone else using Eclipse to do the same?

Cheers
m.b
Title: Re: libusb and Eclipse noob question.
Post by: Jan Axelson on July 27, 2014, 10:52:07 am
Add the path to the project’s Include paths.
Title: Re: libusb and Eclipse noob question.
Post by: Martin on July 27, 2014, 07:57:21 pm
hmm... I wasn't expecting that...  -lusb, or -lusb-1.0 still wont work within eclipse. Fair enough though, a path in the windows world is the fix for all ailments for sure.

I came across a post which advised someone to plug in the "pkg-config --libs libusb" command and then use its output “-lusb” to plug back into the linker,.. tried that still failed.  Any ideas?

m.b
Title: Re: libusb and Eclipse noob question.
Post by: Jan Axelson on July 27, 2014, 09:45:48 pm
By "failed," do you mean that you were able to include the path without error but the project didn't compile? What was the error?
Title: Re: libusb and Eclipse noob question.
Post by: Martin on July 28, 2014, 01:09:39 am
Hi Jan, thanks for your input even though its not directly a USB issue.

I've just (as I write this) successfully compiled my eclipse project). Long story short I was actually correctly adding the -lusb linker command, and also correctly adding the path to the library files. But,...... lesson to oneself, don't add “-lusb” to the libraries section within C++ build settings, but leave out the “-l” in other words add it as “usb” or “usb-1.0”, it seems the “-l” is added internally. At least this is what worked.
Who knew? not me.

BTW:

The error was,

../src/generic_hid.cpp:78: undefined reference to `libusb_init'

and the same type of error for all libusb function your example uses.
Let me know if you want me to elaborate on my steps taken.


Cheers
m.b
Title: Re: libusb and Eclipse noob question.
Post by: Jan Axelson on July 28, 2014, 08:48:02 am
Glad you got it working; thanks for reporting back.