Linking for Windows

[sal55]

I have this program:

#include <windows.h>

int main(void){
 MessageBoxA(0,"One","Two",0);
}

It's compiled like this:

C:\pellesc\bin\pocc.exe /IC:\pellesc\include /IC:\pellesc\include\win -Tamd64-coff -Ze /Ot program.c

producing program.obj, and linked like this:

C:\pellesc\bin\polink /LIBPATH:c:\pellesc\lib  /LIBPATH:c:\pellesc\lib\win64 /OUT:program.exe @filelist

where filelist contains one line with program.obj

However it gives the error:  POLINK: error: Unresolved external symbol '__imp_MessageBoxA'.

What do I have to do to link for Windows? This is for Pelles C 64-bits and runs on 64-bit Windows 7; does MessageBoxA still exist in this version?

Thanks.

[TimoVJL]

MSDN gives that info in here.

Code: [Select]

#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#pragma comment(lib, "user32.lib")
int main(void){
return MessageBoxA(0,"One","Two",0);
}

[sal55]

MSDN gives that info in here.

Code: [Select]

#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#pragma comment(lib, "user32.lib")
int main(void){
return MessageBoxA(0,"One","Two",0);
}

Thanks, that worked. But, I have some questions about this:

o Why can't it just pick up the user32.lib file from the search path I've given it? (Actually why doesn't it just work? With other C compilers (gcc, lccwin, DMC) it doesn't need anything extra to link properly.)

o Will I need one of these for each library such as kernel32.lib etc? (I assume the pragmas are only needed in one module)

o Is there any #if expression I can use to detect that Pelles C is running? (In case I need to turn off the pragma when I want the same code to run on, say, lccwin, which doesn't like the syntax)

[TimoVJL]

o Why can't it just pick up the user32.lib file from the search path I've given it? (Actually why doesn't it just work? With other C compilers (gcc, lccwin, DMC) it doesn't need anything extra to link properly.)

you can, insert it to filelist in own line

o Will I need one of these for each library such as kernel32.lib etc? (I assume the pragmas are only needed in one module)

only one of each and without pragmas too.

o Is there any #if expression I can use to detect that Pelles C is running? (In case I need to turn off the pragma when I want the same code to run on, say, lccwin, which doesn't like the syntax)

__POCC_ as help says

BTW: have you checked povars32.bat from Pelles\bin ?

[Stefan Pendl]

o Why can't it just pick up the user32.lib file from the search path I've given it? (Actually why doesn't it just work? With other C compilers (gcc, lccwin, DMC) it doesn't need anything extra to link properly.)

Some of these compilers resolve dependencies on their own or have more libraries added by default.

[sal55]

you can, insert it to filelist in own line

OK, that worked, thanks. But I'm still puzzled why it couldn't find it in the LIB\WIN64 path I gave it.

__POCC_ as help says

Yes, but I have to find it first! (And even armed with this information, I can't find any trace of it, not in help0009.chm)

BTW: have you checked povars32.bat from Pelles\bin ?

I've tried povars64.bat, but I prefer to do it without having to run this (I can't even remember how to auto-run a batch file!).

[TimoVJL]

__POCC_ as help says

Yes, but I have to find it first! (And even armed with this information, I can't find any trace of it, not in help0009.chm)

Commanline tools -> POCC compiler -> Predefined preprocessor symbols 

BTW: have you checked povars32.bat from Pelles\bin ?

I've tried povars64.bat, but I prefer to do it without having to run this (I can't even remember how to auto-run a batch file!).

Create shortcut with target %COMSPEC% /k c:\PellesC\bin\povars64.bat for console

[Persay]

^^ Thanks i missed that