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I need help with some OpenGL code I am trying to create. Essentially I am trying to create a triangle that is colored green.

Below is the environment, error and code. Can someone please help ?

Env:
Mac OS: High Sierra
Video : Intel HD Graphics 4000 1536 MB graphics

Error Message:

2018-11-14 20:25:46.416648-0800 GLFW opengl[41517:6223602] MessageTracer: load_domain_whitelist_search_tree:73: Search tree file's format version number (0) is not supported

2018-11-14 20:25:46.416773-0800 GLFW opengl[41517:6223602] MessageTracer: Falling back to default whitelist

INFO: OpenGL Version: 2.1 INTEL-10.36.19/n

ERROR: 0:1: '' : Invalid Directive: version440

ERROR: 0:2: '(' : syntax error: syntax error

code :

#include <stdio.h>
#include <string>
#include <vector>
#include <fstream>
#include <algorithm>
#include <stdlib.h>
#include <string.h>

#include <string>
#include <sstream>
#include <iostream>
#include "glew.h"
#include "freeglut.h" // Include the freeGLUT header file

using namespace std;

#define WINDOW_TITLE "Modern OpenGL"

#ifndef GLSL
#define GLSL(Version, source) "#version" #Version "n" #source
#endif

int WindowWidth = 800, WindowHeight = 600;

void UInitialize(int,char*);
void UInitWindow(int,char*);
void UResizeWindow(int,int);
void URenderGraphics(void);
void UCreateVBO(void);
void UCreateShaders(void);

const GLchar * VertexShader = GLSL(440,
 in layout(location=0) vec4 vertex_Postion;
 void main()
 gl_Postion = vertex_Postion;
 
);

const GLchar * FragmentShader = GLSL(440,
 void main()
 gl_FragColor = vec4(0.0f,1.0f,0.0f,1.0f);
 
);


int main(int argc, char* argv)
 UInitialize(argc, argv);
 glutMainLoop();
 exit(EXIT_SUCCESS);


void UInitialize(int argc, char* argv)
 GLenum GlewInitResult;
 UInitWindow(argc, argv);
 GlewInitResult = glewInit();
 if (GLEW_OK != GlewInitResult) 
 fprintf(stderr,"ERROR:%s/n",glewGetErrorString(GlewInitResult));
 
 fprintf(stdout, "INFO: OpenGL Version: %s/n",glGetString(GL_VERSION));
 UCreateVBO();
 UCreateShaders();
 glClearColor(0.0f, 0.0f, 0.0f, 1.0f);


void UInitWindow(int argc, char* argv) GLUT_DOUBLE 

void UResizeWindow(int width, int height)
 glViewport(0, 0, width, height);

void URenderGraphics(void) GL_DEPTH_BUFFER_BIT);
 GLuint totalVertices = 3;
 //creates tirangle
 glDrawArrays(GL_TRIANGLES, 0, totalVertices);
 glutSwapBuffers();

void UCreateVBO(void)
 GLfloat verts=
 0.0f,1.0f,
 -1.0f,-1.0f,
 1.0f,-1.0f
 ;
 float numVertices = sizeof(verts);
 GLuint myBufferID;
 glGenBuffers(1,&myBufferID);
 glBindBuffer(GL_ARRAY_BUFFER,myBufferID);
 glBufferData(GL_ARRAY_BUFFER,numVertices,verts,GL_STATIC_DRAW);
 GLuint floatsPerVertex = 2;
 glEnableVertexAttribArray(0);
 glVertexAttribPointer(0,floatsPerVertex,GL_FLOAT,GL_FALSE,0,0);


void UCreateShaders(void)
 GLuint ProgramId = glCreateProgram();

 GLuint vertexShaderId = glCreateShader(GL_VERTEX_SHADER);
 GLuint fragmentShaderId = glCreateShader(GL_FRAGMENT_SHADER);

 glShaderSource(vertexShaderId,1,&VertexShader,NULL);
 glShaderSource(fragmentShaderId,1,&FragmentShader,NULL);

 glCompileShader(vertexShaderId);
 glCompileShader(fragmentShaderId);

 GLint isCompiled = 0;
 glGetShaderiv(fragmentShaderId, GL_COMPILE_STATUS, &isCompiled);
 char *infoLog;
 int infologLength = 0;
 int charsWritten = 0;
 if(isCompiled == GL_FALSE)
 
 glGetShaderiv(vertexShaderId, GL_INFO_LOG_LENGTH, &infologLength);

 if (infologLength > 0)
 
 infoLog = (char *)malloc(infologLength);
 glGetShaderInfoLog(vertexShaderId, infologLength, &charsWritten, infoLog);
 printf("n%sn",infoLog);
 free(infoLog);
 

 // Provide the infolog in whatever manor you deem best.
 // Exit with failure.
 glDeleteShader(vertexShaderId); // Don't leak the shader.
 return;
 
 fprintf(stdout, "OK!!!!!!!!!");
 glAttachShader(ProgramId,vertexShaderId);
 glAttachShader(ProgramId,fragmentShaderId);

 glLinkProgram(ProgramId);
 glUseProgram(ProgramId);

Read the error message:

ERROR: 0:1: '' : Invalid Directive: version440

ERROR: 0:2: '(' : syntax error: syntax error

this is caused, because the first line in your shader code is:

#version440

but the correct syntax would be #version 440.

This line is automatically generated by the macro GLSL. You have to insert a blank at the end of "#version", so it has to be:

#ifndef GLSL
#define GLSL(Version, source) "#version " #Version "n" #source
#endif

There is a typo in you vertex shader program. It has to be gl_Position instead of gl_Postion.

You have to check the compilation state of the vertex shader and fragment shader separately:

GLint isCompiled = 0;

glCompileShader(vertexShaderId);
glGetShaderiv(vertexShaderId, GL_COMPILE_STATUS, &isCompiled);
if ( isCompiled == GL_FALSE )

 GLint infologLength;
 glGetShaderiv(vertexShaderId, GL_INFO_LOG_LENGTH, &infologLength);
 std::vector< char >infoLog(infologLength);
 GLsizei charsWritten;
 glGetShaderInfoLog(vertexShaderId, infologLength, &charsWritten, infoLog.data());
 std::cout << "compile error:" << std::endl << infoLog.data() << std::endl;
 // .....


glCompileShader(fragmentShaderId);
glGetShaderiv(fragmentShaderId, GL_COMPILE_STATUS, &isCompiled);
if ( isCompiled == GL_FALSE )

 GLint infologLength;
 glGetShaderiv(fragmentShaderId, GL_INFO_LOG_LENGTH, &infologLength);
 std::vector< char >infoLog(infologLength);
 GLsizei charsWritten;
 glGetShaderInfoLog(fragmentShaderId, infologLength, &charsWritten, infoLog.data());
 std::cout << "compile error:" << std::endl << infoLog.data() << std::endl;
 // .....