{"id":163,"date":"2014-02-04T17:39:31","date_gmt":"2014-02-04T17:39:31","guid":{"rendered":"http:\/\/visualgdb.com\/w\/?p=163"},"modified":"2017-10-11T16:09:43","modified_gmt":"2017-10-11T23:09:43","slug":"porting-linux","status":"publish","type":"post","link":"https:\/\/visualgdb.com\/tutorials\/porting\/linux\/","title":{"rendered":"Porting a Windows App to Linux with Visual Studio"},"content":{"rendered":"

This tutorial shows how to port a simple Windows application to Linux by creating a Linux configuration in a Visual Studio project with VisualGDB.<\/p>\n

Before we begin, ensure that VisualGDB 4.0<\/a> or later is installed.<\/p>\n

    \n
  1. Our first step will be to create a simple console application for Windows. Start Visual Studio and select File->New->Project. \"01-newproj\"<\/a><\/li>\n
  2. \u00a0Select “Win32 Console Application”:\"02-consoleapp\"<\/a><\/li>\n
  3. Proceed with the default settings and press “Finish”. Visual Studio will create a basic console application. Add the following code to the main file:\n
    #include \"stdafx.h\"\r\n#include <stdio.h>\r\n#include <stdlib.h>\r\n\r\nint _tmain(int argc, _TCHAR* argv[])\r\n{\r\n    printf(\"HOMEPATH=%s\\n\", getenv(\"HOMEPATH\"));\r\n    printf(\"HOME=%s\\n\", getenv(\"HOME\"));\r\n    return 0;\r\n}<\/pre>\n<\/li>\n
  4. Build the project. If the build complains about the getenv() function, add the following line to the beginning of stdafx.h<\/strong>:\n
    #define _CRT_SECURE_NO_WARNINGS<\/pre>\n
    Run the project and observe its output. Note that on Windows the HOME variable is undefined:\"03-sourcecode\"<\/a><\/li>\n
  5. Now we will create a new Linux configuration for the project. Select Project->Add VisualGDB Configuration->New Linux Configuration<\/strong>:\"04-newcfg\"<\/a><\/li>\n
  6. VisualGDB will start the Linux Configuration Wizard. Enter “LinuxDebug” as the configuration name:\"05-summary\"<\/a><\/li>\n
  7. On the next page select the Linux computer you want to use. You can also select a different toolchain:\"06-linuxcomp\"<\/a><\/li>\n
  8. The last page allows specifying the location of the source files on the Linux machine. You can proceed with the default settings:\"07-sourcelocation\"<\/a><\/li>\n
  9. When you press Finish, VisualGDB will create a new project configuration and a corresponding solution configuration. As certain Windows-specific files are missing on the Linux machine, the compilation will fail with several errors. We will fix them in the next steps:\"12-errors\"<\/a><\/li>\n
  10. Open the stdafx.h file and remove references to SDKDDKVer.h<\/strong> and tchar.h<\/strong>:\"13-linux\"<\/a><\/li>\n
  11. Rename _tmain()<\/strong> to main()<\/strong> and replace _TCHAR<\/strong> with char<\/strong>. Build the project. You will notice that the modified source files will be transferred to the Linux machine and built there using GCC, the standard compiler on Linux systems:\"14-buildok\"<\/a><\/li>\n
  12. Set a breakpoint on the return<\/strong> statement and run the program. Observe the output:\"15-debug\"<\/a><\/li>\n
  13. As Windows and Linux use different variable names (HOMEPATH vs HOME), we had to write two separate getenv()<\/strong> lines. Now we will add conditional compilation statements to ensure that only one line is used on each OS. We could test for the _MSC_VER<\/strong> macro on Windows (that is set by the Visual C++ compiler) or the LINUX<\/strong> macro that is defined by Linux headers, however in this tutorial we will show how to add your own macro. Right-click on the project, select VisualGDB Project Properties and go to the Makefile Settings page. Add BUILDING_FOR_LINUX<\/strong> to Preprocessor Macros:\"16-macro\"<\/a><\/li>\n
  14. Now press OK and add the #ifndef BUILDING_FOR_LINUX<\/strong> statement to your code. Build and run the program. Observe that the output only contains one line now:\"17-ifdef\"<\/a><\/li>\n
  15. Now switch the current configuration back to Debug and hit F5 to run the Windows version of your program:\"18-windows\"<\/a><\/li>\n
  16. As most of the API (except for the basic standard functions) is different between Linux and Windows, you may want avoid having too many #ifdef<\/strong> statements and simplify your porting. You can accomplish this in one of the following ways:\n