DevCpp-Mingw Install & Compilation					Sept 2005

This document should be included with curl-7.14.0.tar.gz (or latest version) under  \packages\Win32\Dev-Cpp folder.

Reference Emails available at curl@haxx.se: 
Libcurl Install and Use Issues
Awaiting an Answer for Win 32 Install 
res = curl_easy_perform(curl); Error
Makefile Issues

Having previously done a thorough review of what was available that met my requirements under GPL, I settled for Libcurl as the software of choice for many reasons not the least of which was the support.

Background

This quest started when I innocently tried to incorporate the libcurl library into my simple source code. I figured that a few easy steps would accomplish this without major headaches. I had no idea that I would be facing an almost insurmountable challenge. 

The main problem lies in two areas. First the bulk of support for libcurl exists for a Unix/linux command line environments. This is of little help when it comes to Windows O/S.

Secondly the help that does exist for the Windows O/S focused around mingw thru a command line argument environment. 

You may ask "Why is this a problem?"

I'm using a Windows O/S  with DevCpp. For those of you who are unfamiliar with DevCpp, it is a window shell GUI that replaces the command line environment for gcc. A definite improvement that I am unwilling to give up. However using DevCpp presented its own set of issues. Inadvertently I also made some careless errors such as compiling the 7.14 version of Makefile with an older version of source code. Thanks to Dan Fandrich   for picking this up.

I did eventually with the help of Daniel, Phillipe and others manage to implement successfully (the only mingw available version) curl-7.13.0-win32-ssl-devel-mingw32 into the DevCpp environment. Only the dynamic libcurl.dll libcurldll.a libraries worked. The static library which I was interested in did not. Furthermore when I tried to implement one of the examples included with the curl package (get info.c) it caused the executable to crash. Tracing the bug I found it in the code and function res = curl_easy_perform(curl);. 

At this point I had to make a choice as to whether invest my limited time-energy resource to fixing the bug or to compile the new version available. After searching the archives I found a very similar or the same bug reported from version 7.12x on. Daniel did inform me that he thought that this bug had been fixed with the latest version. So I proceeded to compile the latest SSL version where I faced other challenges.

In order to make this process unremarkable for others using the same environment I decided to document the process so that others will find it routine. It would be a shame if newbies could not implement this excellent package for their use.

I would like to thank the many others in this forum and in the DevCpp forum for their help. Without your help I may either have given up or it would have taken me many times longer to achieve success.

The Cookbook Approach

This discussion will be confined to a SSL static library compilation and installation. Limited mention and comments will be inserted where appropriate to help with non-SSL, dynamic libraries and executables.

Using Makefile from DevCpp to compile Libcurl libraries

Preamble

Using the latest version release - curl-7.14.0.tar.gz. Curl source code is platform independent. This simply means that the source code  can be compiled for any Operating System (Linux/Unix Windows etc. and variations of thereof).

The first thing to note is that inside curl-7.14.0 you will find two folders lib and src. Both contain Makefile.m32 (required for win mingw library or exe compilation) files which are different. The main difference between these two folders and the makefiles is that the src folder contents are used to compile an executable file(curl.exe) while the lib folder contents are used to compile a static (libcurl.a) and dynamic (libcurl.dll & libcurldll.a) file that can be used to compile libcurl with your own source code so that one can use and access all libcurl functions.

Before we start please make sure that DevCpp is installed properly. In particular make sure you have no spaces in the name of any of the directories and subdirectories where DevCpp is installed. Failure to comply with the install instructions may produce erratic behaviour in DevCpp. For further info check the following sites

http://aditsu.freeunixhost.com/dev-cpp-faq.html
http://sourceforge.net/forum/message.php?msg_id=3252213

As I have mentioned before I will confine this to the SSL Library compilations but the process is very similar for compilation of the executable - curl.exe; just substitute the src folder makefile in its stead.

First use a text processor Notepad, or your own favourite text processor. To engage your favourite text processor, select Makefile.m32 click once with your mouse on file icon; icon turns blue, press the shift key and right-click on mouse, menu appears select "Open with",  select your favourite text processor. 

Next read the contents of Makefile.m32. It includes instructions on its use.

Method I - DOS Command Line
 
Note - The only reason I have included this method is that Method II which is the preferred method for compiling does not allow for the setting of option switches (e.g. SSL = 1 or SSL =0). At least that's what they tell me at the Dev-Cpp forum.

1 - Make a copy of (D:\Dev-Cpp\bin) bin folder and name it "bin Original" place it in 
the Dev-Cpp installed directory (D:\Dev-Cpp\ for this example)

2 - Copy the entire contents of the LIB folder of curl-7.14.0.tar.gz or zip version into the bin folder above (D:\Dev-Cpp\bin). The reason being is that the make.exe file resides in this folder. Make.exe will use - Makefile.m32, Makefile.inc, and the source code included in the lib folder to compile the source code. There is a PATH issue with make.exe that remains unresolved at least for me. Unless the entire source code to be compiled is placed entirely within the directory of make.exe an error message will be generated - "file xxxx.yyy not available".

3- Go to Dev-Cpp\bin and double click on make .exe. You will see a DOS window quickly pop up and close very quickly. Not to worry! Please do not skip this step.

4- Click on the start button\Programs\MS-DOS Prompt.Once the DOS Window is up Type the disk drive letter (e.g. E: ) engage the enter button. The path should automatically take you to the directory of the make.exe file.

5- To compile the source code simply type at the DOS prompt  make -f Makefile.m32 as per instructions contained in the Makefile.m32 file (use any text processor to read instructions). I don't believe that this makefile allows for the option of non SSL. Ignore any warnings. 

6- Collect and make copies of libcurl.a, libcurl.dll, libcurldll.a and any *.o compilations you might need in another directory outside of the bin directory as you will need this files shortly to set up libcurl for use with Dev-cpp. For most apps *.o is not required. Later on we will show what to do with these files.

7- You are finished but before closing we need to do cleanup - erase the bin folder and rename the "bin Original" folder created in step 1 to bin.

Note to compile a curl executable the process is probably similar but instead of using the LIB folder contents use the SRC folder contents and Makefiles in curl-7.14.0.tar.gz. File directories relative placements must be respected for compiling to take place successfully. This may not be possible with the PATH problem that make.exe experiences. If anyone has solved this PATH issue and please make sure it  actually works on Win 9x/2000/XP before letting me know. Then please let me or Daniel in on the solution so that it can be included with these instructions. Thanks.

or

Method II - Dev-Cpp GUI

1- Copy the entire contents of the LIB folder of curl-7.14.0.tar.gz or zip version into  any folder outside of  (Dev-Cpp\bin).

2- Drop the File/New/click on Project.

3- New Project Dialogue box appears. Double click on the Static Library.

4- Create Project Dialogue box appears. Select the LIB folder location to place and locate your Project File Name. Placing the Project File Name elsewhere may cause problems (PATH issue problem again).

5- Drop down the Project/Project Options. Project Options Dialogue box appears.

6- Select the Makefile tab in the Project Options Dialogue Box. Check Box - Use Custom Makefile. Click on the Folder icon at the extreme right of the Check Box. Select Makefile.m32 in the folder wherever you have placed the contents of the LIB Folder. Press OK and close the Dialogue Box.

7- Drop the Menu Project/Click on Add to Project. Open File Dialogue Box appears. 
The Dialogue Box should open in the folder wherever you have placed the contents of the LIB Folder. If not go there.

8- Select Crtl-A to select all files in the LIB folder. Click on open to add files and close box. Wait till all files are added. This may take 30 seconds or longer.

9- Drop the Menu Execute/Click on Compile. 

10- That's it.

The following steps must be completed if Curl is to work properly.

LIB folder inclusions (*.a placement)

1- Refer to Method I - DOS Command Line point # 6 Take libcurl.a, libcurldll.a
and install it in the directory C( or whichever drive Dev is installed) :\Dev-Cpp\lib.

Include Folder

1- Create a new folder by the name of curl (do not change the name curl to some other name as it will cause major issues)  in the directory C:\Dev-Cpp\include.

2- Copy the entire contents of the curl folder of curl-7.14.0.tar.gz or zip version into  
 the newly created curl directory - C:\Dev-Cpp\include\curl.

Links To Include And Lib Folder

1- Drop the Menu - Tools\Compiler Options\Directories\Libraries. Make sure that 
C( or whichever drive Dev is installed):\DEV-CPP\lib is included.

2- Next select the Menu - Tools\Compiler Options\Directories\C Includes. Make sure that C:\DEV-CPP\include and C:\Dev-Cpp\include\curl are included.

3- Next select the Menu - Tools\Compiler Options\Directories\C++ Includes. Make sure that C:\DEV-CPP\include and C:\Dev-Cpp\include\curl are included.

Linker Links

1- Drop the Menu - Tools\Compiler Options\Directories\Compiler. 

2- Make sure that the box "Add these commands to the linker command line" is checked.

3- Include in the white space immediately below the box referred in 2 -lcurl -lws2_32  -lwinmm.

SSL Files

1- Get the latest openSSL (as of time of this writing) openssl-0.9.7e-win32-bin.zip for the minimalist package of the openssl-0.9.7e binaries ported to MS Windows 95/98/NT/XP using the MingW32/GCC-3.1 development environment. The file may be downloaded at http://curl.haxx.se/download/. 

2- Open the above zip file. You will find two files - SDL.dll, SDL_mixer.dll. Install them in the directory C:\WINDOWS\SYSTEM32 for Win 9x users and c:\winnt\system32 for NT-family users.

Multithreading Files

To be completed

#define

1- Make sure that your program includes the following - #define CURL_STATICLIB 
must be declared FIRST before any other define functions may be added. Otherwise you may experience link errors.

2- Don't forget to include   #include "curl/curl.h".

e.g.
    #define CURL_STATICLIB 
#include <windows.h>
    #include "curl/curl.h"
#include <fstream>
#include <iostream>
#include <vector>
etc...

Static or Dynamic Library

The above steps apply for the use by a static library. Should you choose to use a dynamic library you will be required to perform these additional steps.

1- Refer to Method I - DOS Command Line point # 6. Install libcurl.dll in the directory C:\WINDOWS\SYSTEM32 for Win 9x users and c:\winnt\system32 for NT-family users.

2- Refer to Linker Links point 3 - Replace -lcurl with -lcurldll.

Voila you're done.

The non-SSL static Library build may not be possible to use at least as of the time of this writing - v7.14. Check reference emails - Phillipe and I found it impossible to fully compile as certain files were missing for linking. No big loss as SSL is a major plus.

Hope this Helps

Tom