Solved Compiler path to header files

[Phishfry]

I am going to do the tutorials in "Foundations of GTK" book and I am wondering if my paths for compiling are setup correctly.
Where would I modify to include gtk.h.
My header currently uses the whole path to find gtk.h and that works.
It does not seem like this is correct as most tutorials use /gtk/gtk.h as the header path.
Am I doing the right thing?
/usr/local/include does not seem to be included in the compiler header path but /usr/include is.
It seems like my `pkgconf` part of my compile command may be wrong.
Can I get some guidance please. Most examples use gcc versus clang. Should I be using gcc?
Here is my compile command:
cc `pkgconf --cflags gtk+-3.0` first.c -o first.app `pkgconf --libs gtk+-3.0` -rdynamic -Wall

My first assignment:

#include </usr/local/include/gtk-3.0/gtk/gtk.h>

int main(int argc, char *argv[]) {

  GtkWidget *window;

  gtk_init(&argc, &argv);

  window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
  gtk_window_set_title (GTK_WINDOW (window), "First Project");
  gtk_widget_show(window);

  g_signal_connect(window, "destroy",
      G_CALLBACK(gtk_main_quit), NULL);

  gtk_main();

  return 0;
}

 

[Phishfry]

I fooled with moving the path from the gtk.h header to the CFLAG option for compiling.
cc `pkgconf --cflags /usr/local/include/gtk-3.0` first.c -o first.app `pkgconf --libs /usr/local/include/gtk-3.0` -rdynamic -Wall
But that failed. The compiler gave some good tips. I need to look at the search path for pkgconf compiling option.

Package /usr/local/include/gtk-3.0 was not found in the pkg-config search path.
Perhaps you should add the directory containing `/usr/local/include/gtk-3.0.pc'
to the PKG_CONFIG_PATH environment variable
Package '/usr/local/include/gtk-3.0', required by 'virtual:world', not found
Package /usr/local/include/gtk-3.0 was not found in the pkg-config search path.
Perhaps you should add the directory containing `/usr/local/include/gtk-3.0.pc'
to the PKG_CONFIG_PATH environment variable
Package '/usr/local/include/gtk-3.0', required by 'virtual:world', not found
first.c:1:10: fatal error: '/gtk/gtk.h' file not found
#include </gtk/gtk.h>
         ^~~~~~~~~~~~
1 error generated.

 

[SirDice]

Not much of a programmer but you can get a list of "packages" by using pkgconf --list-all. One of the packages that's installed on my system is called gtk+-3.0, and you can use it like this: pkgconf --libs 'gtk+-3.0' and it will print a line of compiler options providing the include files and library locations.

# pkgconf --libs 'gtk+-3.0'
-L/usr/local/lib -lgtk-3 -lgdk-3 -lpangocairo-1.0 -lpango-1.0 -latk-1.0 -lcairo-gobject -lcairo -lpthread -lgdk_pixbuf-2.0 -lgio-2.0 -lgobject-2.0 -lglib-2.0 -lintl

Note though that I used GTK+ as an example, you would need to find the correct one for your situation. But this should provide you some clues on how to use it.

 

[elephant]

Set the "I" and "L" switches to point to /usr/local/include and /usr/local/lib.

eg. cc first.c -I/usr/local/include -L/usr/local/lib -o first.app

 

[Phishfry]

I fixed this by dropping off -rdynamic from the compiler.
With SirDice advice I could tell that pkgconf was OK. So I looked elsewhere.

root@E6420:/gtk # pkgconf --libs 'gtk+-3.0' -L/usr/local/lib -lgtk-3 -lgdk-3 -lpangocairo-1.0 -lpango-1.0 -latk-1.0 -lcairo-gobject -lcairo -lpthread -lgdk_pixbuf-2.0 -lgio-2.0 -lgobject-2.0 -lglib-2.0 -lint

 

[Juanmi Taboada]

I like to have source code verification and linting in my vim editor while coding. To resolve this in a general manner I configured the next environment variables in my shell (~/.profile or ~/.bashrc):

# Where to look for includes
export CPATH="$CPATH:/usr/local/include"

# Where to look for packages when working with pkgconf
export PKG_CONFIG_PATH="$PKG_CONFIG_PATH:/usr/local/binary/libs/includes/pkgconfig/"

This resolved any issue with /usr/local/... for vim and any other command I executed in the shell.