// The index returned from these GLint functions gets passed to {%glEnableVertexAttribArray} during rendering.

GLint position_attrib_index = {%glGetAttribLocation}(program, "position"); // program is what is returned by {%glCreateProgram}.

GLint texcoord_attrib_index = {%glGetAttribLocation}(program, "texcoord");

GLint normal_attrib_index = {%glGetAttribLocation}(program, "normal");

GLint color_attrib_index = {%glGetAttribLocation}(program, "color");

{%glBindFragDataLocation}(program, 0, "output_color"); // "output_color" is an output value in your vertex shader and an input value in your fragment shader.

GLint num_uniforms;

{%glGetProgramiv}(program, GL_ACTIVE_UNIFORMS, &num_uniforms);

GLchar uniform_name[256];

GLsizei length;

GLint size;

GLenum type;

for (int i = 0; i < num_uniforms; i++)

{%glGetActiveUniform}(program, i, sizeof(uniform_name), &length, &size, &type, uniform_name);

// ... save this uniform data so it can be used during rendering

}