next »

[Massena]

First of all, hi! :D I'm beginning to program in c++ using allegro and I ran into some early trouble. You see, these two questions don't actually stop me from programming but they're just frustrating annoyances. First of all I'm running Mac OS 10.4 and these are my problems: How do you compile a small program with allegro on the command line, I mean, I've been using xCode but I like the command-line better for now so I tried "gcc example.cpp -framework Allegro" and it returns the oddest of bugs:

Code:

/usr/bin/ld: Undefined symbols:
_main
collect2: ld returned 1 exit status

(What the hell?)
Note that I can use the command line to compile pure c++ programs and xCode to compile allegro applications.
Secondly when I have to put a path in an allegro application I see many examples that just use "example.bmp" but the only way I can get it to work is by putting the full path even thought the file is in the same directory as the code. How could I make it so that I don't have to go around looking for full paths?
Anyways thanks very much in advance, congratulations for the great site!

[Redwire]

For the pathname did you use "example.bmp" or "./example.bmp"
and for the command-line problem I don't know about mac but you should try
gcc example.cpp -o example -lallegro

oh and welcome aboard

[ravuya]

-framework will take care of the library linkage and include paths.

I think Allegro does something funky to the main function in your code; check the documentation for it or ask on the mailing list. IIRC, there's a macro you need to define.

[Massena]

For the pathname did you use "example.bmp" or "./example.bmp"
and for the command-line problem I don't know about mac but you should try
gcc example.cpp -o example -lallegro

oh and welcome aboard

Thanks
I tried both, none worked and -lallegro doesn't seem to work

-framework will take care of the library linkage and include paths.

I think Allegro does something funky to the main function in your code; check the documentation for it or ask on the mailing list. IIRC, there's a macro you need to define.

Hm.. I have no idea what could it could be doing since the same code works on xcode, using the same framework. As for macros, I have no clue on what are macros or how to define one.   
Anyways thanks for the speedy response!

[Zaphos]

I think Allegro does something funky to the main function in your code; check the documentation for it or ask on the mailing list. IIRC, there's a macro you need to define.

I assume you're referring to END_OF_MAIN() which should appear after the body of the main() function.
Like:

Code:

int main()
{
 // etc
 return 0;
} END_OF_MAIN() // <-here

[Massena]

I think Allegro does something funky to the main function in your code; check the documentation for it or ask on the mailing list. IIRC, there's a macro you need to define.

I assume you're referring to END_OF_MAIN() which should appear after the body of the main() function.

Why should END_OF_MAIN () be undefined, doesn't the library define it? I'll try alegro.cc's forums and I'll post back if I can solve this problem

[Zaphos]

I think Allegro does something funky to the main function in your code; check the documentation for it or ask on the mailing list. IIRC, there's a macro you need to define.

I assume you're referring to END_OF_MAIN() which should appear after the body of the main() function.

Why should END_OF_MAIN () be undefined, doesn't the library define it? I'll try alegro.cc's forums and I'll post back if I can solve this problem

Er, I never said it should be undefined.  The library does define it.  You just have to use it.

Allegro.cc would be an excellent place to also ask your question, though.

edit: ah, right, ravuya said you needed to define it.  I assumed he might have been just mis-remembering, though.

[ravuya]

I mistyped, sorry. It was a pretty hectic day when I made that post.

You might want to look at the project file in Xcode; it should tell you inside one of the Target properties which additional command line arguments are being used. I seem to remember there was more than one framework that got used with Allegro under OS X, but that was years ago.

[Massena]

I did it! It seems that linking allegro is quite complicated so the library provides a script, allegro-config, that does that for the user so after I put /usr/local/bin in my path and made sure END_OF_MAIN() was there all it took was a simple

Code:

g++ example.cpp `allegro-config --libs`

command to compile the program.
Thanks!