[Jack-Devel] FW: Jack beginner question - which files are Jack's library files?

I a still trying to get a simple Jack program to compile (Ubuntu 13.04 64 bit)

The problem seems to be that even when I point gcc toward the folder where the Jack libraries are, the compiler reports undefined reference errors.

For example,
If I run gcc with no libraries, I get undefined reference errors:

val@zar:~/JackFiles/testJack$ gcc -o metronome   metro.c
/tmp/cc4akFsZ.o: In function `signal_handler':
metro.c:(.text+0x16): undefined reference to `jack_client_close'
/tmp/cc4akFsZ.o: In function `process_silence':
metro.c:(.text+0x81): undefined reference to `jack_port_get_buffer'
/tmp/cc4akFsZ.o: In function `process_audio':
....
Here I tried both a -L and a -l parameter:
val@zar:~/JackFiles/testJack$ gcc -o metronome -L/usr/lib/x86_64-linux-gnu -ljack metro.c

/tmp/ccksW4it.o: In function `signal_handler':
metro.c:(.text+0x16): undefined reference to `jack_client_close'
/tmp/ccksW4it.o: In function `process_silence':
metro.c:(.text+0x81): undefined reference to `jack_port_get_buffer'
/tmp/ccksW4it.o: In function `process_audio':
...

I get the same errors if I omit the -L with path to the libjack.so files
val@zar:~/JackFiles/testJack$ gcc -o metronome  -ljack metro.c

/tmp/cc5oyTHv.o: In function `signal_handler':
metro.c:(.text+0x16): undefined reference to `jack_client_close'
…
And the same if I include the -L and omit the -l
val@zar:~/JackFiles/testJack$ gcc -o metronome -L/usr/lib/x86_64-linux-gnu  metro.c

/tmp/cchbhuv2.o: In function `signal_handler':
metro.c:(.text+0x16): undefined reference to `jack_client_close'
...

All this makes me feel that the files that I think are Jack's library files are not in fact the library files or the files are 'incorrect' in some way.
Here are my Jack library files:
val@zar:/usr/lib/x86_64-linux-gnu$ find libjack*
libjack.a
libjackserver.a
libjackserver.so
libjackserver.so.0
libjackserver.so.0.0.28
libjack.so
libjack.so.0
libjack.so.0.0.28

Any suggestions?  Does anyone have Ubuntu compiling Jack?  If so, what do your libraries look like and where are they and how do you connect them to gcc?

Thanks for any suggestions.

Val Veirs
Professor of Physics




________________________________________
From: Val Veirs (R)
Sent: Wednesday, August 21, 2013 12:44 PM
To: Florian Paul Schmidt
Subject: RE: [Jack-Devel] Jack beginner question

First, “Thank you” to Pawel and Flo for helping me as I try to compile anything with jack.

I have now installed libjack-dev and one result seems to be that I now have a path and file:
/usr/include/jack/jack.h
which I take to be a good thing.
When I try to compile, now the compiler now finds jack.h but none of its references resolve.  I now need to be linked into some jack library(s) that either I don't yet have or I have them in one or more wrong locations.
Compiling metro.c yields:
val@zar:~/JackFiles/jack-1.9.9.5/example-clients$ gcc -o metronome `pkg-config --cflags --libs jack` metro.c
/tmp/ccnO5ZRZ.o: In function `signal_handler':
metro.c:(.text+0x16): undefined reference to `jack_client_close'
/tmp/ccnO5ZRZ.o: In function `process_silence':
metro.c:(.text+0x81): undefined reference to `jack_port_get_buffer'
/tmp/ccnO5ZRZ.o: In function `process_audio':
metro.c:(.text+0xc3): undefined reference to `jack_port_get_buffer'
/tmp/ccnO5ZRZ.o: In function `process':
metro.c:(.text+0x214): undefined reference to `jack_transport_query'
/tmp/ccnO5ZRZ.o: In function `main':
metro.c:(.text+0x6e2): undefined reference to `jack_client_open'
metro.c:(.text+0x736): undefined reference to `jack_set_process_callback'
metro.c:(.text+0x75c): undefined reference to `jack_port_register'
metro.c:(.text+0x772): undefined reference to `jack_get_sample_rate'
metro.c:(.text+0xb31): undefined reference to `sin'
metro.c:(.text+0xbaf): undefined reference to `jack_activate'
collect2: error: ld returned 1 exit status

I looked to see if Flo's suggested path to jack.pc existed and found that my jack.pc is one directory farther down at: /usr/lib/x86_64-linux-gnu/pkgconfig

I tried setting:
 PKG_CONFIG_PATH=/usr/lib/x86_64-linux-gnu/pkgconfig; export PKG_CONFIG_PATH
and confirmed that this setting worked:
 printenv PKG_CONFIG_PATH
/usr/lib/x86_64-linux-gnu/pkgconfig

But, compiling again did not change the failure to find the needed links to the jack.h entry points (jack_client_close etc.)

I have messed with jack so much now that I may have made it impossible to get a working combination of files and paths and libraries.

But, I so much need further advice!

Thanks in advance,
Val Veirs
Colorado College
________________________________________
From: [hidden] [[hidden]] on behalf of Florian Paul Schmidt [[hidden]]
Sent: Wednesday, August 21, 2013 6:01 AM
To: [hidden]
Subject: Re: [Jack-Devel] Jack beginner question

On 21.08.2013 08:15, Val Veirs (R) wrote:
> Greetings,
>
> I am just beginning to look at Jack.  I am running Ubuntu 13.04 and I installed the binaries and QJackCtrl seems to work just fine.  That makes me think that so far I have the deamon running as it should.
>
> I want to compile just the simplest of your example clients programs to get started.
>   I download the Jack sources and put them in my user space.  There I find metro.c.  In a terminal window I try to compile and I run into path problems.
>
> Here is what is reported:
>
> val@zar:~/JackFiles/jack-1.9.9.5/example-clients$  gcc -o metronome `pkg-config --cflags --libs jack` metro.c
>
> Package jack was not found in the pkg-config search path.
> Perhaps you should add the directory containing `jack.pc'
> to the PKG_CONFIG_PATH environment variable
> No package 'jack' found
> metro.c:30:23: fatal error: jack/jack.h: No such file or directory
> compilation terminated.
>
>
> I guess my question is what should PKG_CONFIG_PATH point to?
>
> I would appreciate any suggestions.

Like some other people mentioned, you need the -dev packages for
libjack. But the metro client should be available in the (some) jack
package. It's called jack_metro. You could also try tools like jack_lsp
to check if the daemon is running fine..

But just to answer your question: pkg-config looks in some default paths
for .pc files. One of them should be /usr/lib/pkgconfig. If you want it
to search additional paths, then you can point it to e.g.
/usr/local/lib/pkgconfig, this is where the .pc files of packages are
often put when you build the packages yourself from source and leave the
default prefix /usr/local unchanged. Installing libjack-dev (or whatever
it's called) should give you /usr/lib/pkgconfig/jack.pc. So no need to
adjust the PKG_CONFIG_PATH..

Have fun,
Flo

> Val Veirs
> Colorado College
> Colorado Springs
> 
> Jack-Devel mailing list
> [hidden]
> http://lists.jackaudio.org/listinfo.cgi/jack-devel-jackaudio.org

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