vala: Gst namespace could not be found - gstreamer

I have some problems with "vala", when using gstreamer namespace "Gst"
vala cannot recognise it...can somebody help me please?
Error: Gst namaspace could not be found
I'm new to vala so I don't know what to do to resolve it

You need to pass something like --pkg gstreamer-1.0 to valac when compiling.
Any packages you want to use you need to tell the compiler about. There are 34 packages distributed with valac which use the "Gst" namespace, and you don't give any information about what you're actually trying to do… Most of the basic stuff is in gstreamer-1.0 (or, if you're using 0.10, gstreamer-0.10), but you'll likely end up using at least a couple others.

Related

Is it possible to use Kotlin Native on macOS 10.12?

I'm trying to port a simple Go macOS application over to Kotlin Native. After struggling with various errors I decided to take a step back, and have a look at the official examples provided with Kotlin Native.
I found a basic OpenGL example here:
https://github.com/JetBrains/kotlin-native/tree/master/samples/opengl
But so far I haven't been able to get this to compile.
I tried downloading the complete sources for Kotlin, but that wont build. I followed a few suggestions generated at build time, including the change to 'ignoreXcodeVersionCheck' and downloading prebuilt binaries for the compiler, but at this point I'm wondering if this just isn't supported by my environment? I do understand that this is all experimental.
I've attached a sample of errors below, but I'm not sure whats relevant.
Question: Does anyone else have this setup / environment working please? can I expect to get it working?
macos 10.12.4, kotlin 1.3.11, xcode 8.2.1
.konan/dependencies/clang-llvm-6.0.1-darwin-macos/include/c++/v1/cmath:551:28: error: expected a qualified name after 'typename'
_LIBCPP_CONSTEXPR typename enable_if<is_floating_point<_A1>::value, bool>::type
.konan/dependencies/clang-llvm-6.0.1-darwin-macos/include/c++/v1/cstddef:44:15: fatal error: 'stddef.h' file not found
#include_next <stddef.h>
A problem occurred evaluating root project 'kotlin-native-master'.
expected Xcode version 10.1, got 8.2.1, consider updating Xcode or use "ignoreXcodeVersionCheck" variable in konan.properties
kotlin-native-master/runtime/src/main/cpp/ObjCExportErrors.mm:73:23: error: no type or protocol named 'NSErrorUserInfoKey'
NSMutableDictionary<NSErrorUserInfoKey, id>* userInfo = [[NSMutableDictionary new] autorelease];
.konan/dependencies/clang-llvm-6.0.1-darwin-macos/include/c++/v1/cmath:313:9: error: no member named 'signbit' in the global namespace
using ::signbit;
I did manage to get a "hello world" working under the above environment, but I have given up with the OpenGL stuff. I cant update my environment currently, and I guess this issue doesn't affect many people. So I'm going to close it with this 'answer'.

GNU libtool: how to convert function call to script

I am new running code in C++ linux environment; so, please accept my apologies in advance if I am asking very trivial question. The only reason that I switched to linux is to run the library linked below. I would consider my C++ coding skills at intermediate level.
I downloaded the code at this location (http://www.jasoncantarella.com/wordpress/software/tsnnls/). Also, needed were Lapack, Blas, Argtable2 which I downloaded before.
Now, I can run the script after changing to relevant directory:
>> cd /home/dkumar/libtsnnls-2.3.3/tsnnls/
>> ./tsnnls_test -A A_01.sparse -b b_01.mat -x x_01.mat --tsnnls
However, when I looked at your code "tsnnls_test.c", the function is defined as:
static void tsnnls_test(taucs_ccs_matrix *A,taucs_double *realx,taucs_double *b)
This function call and script call are very different.
I would like to change the argument list of tsnnls_test function to make it useful for my work. I am not getting successful in just making an executable out of "tsnnls_test.c" and I do not know how script works.
My question: Since the author is not available to answer this question, I would like to ask experts here:
How does this code → script thing works using GNU libtool? How should I try to change it?
Possibly, some guidance on using libtool to load a duplicate function name from a shared library would be helpful.
My intention is to get a fast solver for sparse nonnegative least square solver. If anyone has any suggestion on that, please do share with me.

fatal error: 'libpq++' file not found

I would love to use libpq++ library in my C++ project but I am unable to get it working.
So far, I have installed libpqxx-dev libpqxx-4.0 packages on my Ubuntu 14.04 and provided -llibpq++ to clang++.
However, no matter what I do, I still get following error:
src/serverdata.h:4:10: fatal error: 'libpq++' file not found
It seems that I didn't install libpq++ properly but I don't really see any problem.
Any help would be highly appreciated.
Seems to me, your src/serverdata.h has 4th line like:
#include "libpq++"
If so, change it to something like:
#include <pqxx/basic_connection.hxx>
PS. Files in dev packet are listed here

Musical Notations using Aubio in Xcode

I am trying to make a program for basic monophonic note transciption using aubio, for my high school class. I am trying to run an example code in Xcode and I get these errors:
Apple Mach-O Linker(Id)Error
"_CFStringCreateWithCString", referenced from:
Any advice on how to fix these errors, or on note transcription using aubio in Xcode would be appreciated! Thanks!
You will need to link against CoreFoundation, AudioToolbox, and Accelerate system frameworks, as well as the aubio framework.
Please ask your questions # https://github.com/aubio/aubio/issues.
Also check out http://www.denemo.org, which does monophonic transcription to score using aubio.

can't get pcre to work in c++

I'm pretty new to c++, as in I'm still learning the basic of it
anw. I want to use pcre in it, but have so far been unsuccessful in getting it to work.
I'm running Ubuntu and have in my latest attempt tried to install the libpcre3-dev package (I should mention that I am rather new to Linux too)
I included pcre with
#include <pcrecpp.h>
currently I'm getting the error "undefined reference to pcrecpp::RE::no_arg" whenever I try to define an RE object
pcrecpp::RE reg("fys|smi|int|fok|arv|kar");
Can anyone explain to me what I'm doing wrong, and or give me a step by step guide on how to do it.
And I do know that c++ have a regex library, but since I'm used to pcre from php, that is what I'm going for
You should pass -lpcrecpp on the command line to link your program with the PCRE library. Just including the declarations in a header file is not enough.