DaniWeb Forum Index > Software Development > C

C RSS

Including files at run time

Last »

•

Join Date: Oct 2006

Posts: 514

Reputation: Jishnu will become famous soon enough

Solved Threads: 26

Jishnu

Offline

Posting Pro

Including files at run time

Dec 21st, 2007

Hello,

I know this much that I want to include two files in my program. But can I decide which files to include at run time? Is this possible?

Thanks in advance,
-Jishnu.

"You know you're a computer geek when you try to shoo a fly away from the monitor screen with your cursor. That just happened to me. It was scary." - Juuso Heimonen.

"The only truly secure computer is one buried in concrete, with the power turned off and the network cable cut." - Anonymous.

•

Join Date: Dec 2006

Posts: 241

Reputation: ssharish2005 is on a distinguished road

Solved Threads: 20

ssharish2005 ssharish2005 is offline

Offline

Posting Whiz in Training

Re: Including files at run time

Dec 21st, 2007

Cant you use ifndef-else-endif directives?

EDIT: Run time, i wonder you could.

ssharish

Last edited by ssharish2005; Dec 21st, 2007 at 6:23 am.

•

Join Date: Dec 2005

Posts: 5,850

Reputation: Salem has a reputation beyond repute

Solved Threads: 749

Salem

Offline

Void main'ers are DOOMed

Re: Including files at run time

Dec 21st, 2007

The simple way is to just compile the whole code, then have some kind of decision in the code, like this.

 Help with Code Tags 
 C Syntax (Toggle Plain Text) 
int main ( ) {
  if ( something ) {
    program1();
  } else {
    program2();
  }
}
int main ( ) {
  if ( something ) {
    program1();
  } else {
    program2();
  }
}

A more complicated way would be to write each separate module as a DLL, then at run-time you can choose which library instance to access.

•

Join Date: Dec 2006

Posts: 241

Reputation: ssharish2005 is on a distinguished road

Solved Threads: 20

ssharish2005 ssharish2005 is offline

Offline

Posting Whiz in Training

Re: Including files at run time

Dec 21st, 2007

Salem if that was possible, how can we include the .so file at run time?

ssharish

•

Join Date: Oct 2006

Posts: 514

Reputation: Jishnu will become famous soon enough

Solved Threads: 26

Jishnu

Offline

Posting Pro

Re: Including files at run time

Dec 21st, 2007

•

EDIT: Run time, i wonder you could.

Sorry, I could not understand what you mean.

•

The simple way is to just compile the whole code, then have some kind of decision in the code, like this.

But inside the functions program1() and program2(), how can I include a file?

•

Join Date: Oct 2007

Posts: 1,951

Reputation: Duoas has much to be proud of

Solved Threads: 214

Duoas

Offline

Posting Virtuoso

Re: Including files at run time

Dec 21st, 2007

What do you mean by "include a file"?

Are you talking about source code?
Or binary data (pictures, music, etc.)?
Or just regular text (ASCII, RTF, etc.)?

How do you want it to be used at runtime? And what difference does it make whether you include one or the other?

Answer these three and we'll have an easier time answering you...

Hope this helps.

•

Join Date: Aug 2005

Posts: 15,343

Reputation: Ancient Dragon has a reputation beyond repute

Solved Threads: 1460

Ancient Dragon Ancient Dragon is offline

Offline

Still Learning

Re: Including files at run time

Dec 21st, 2007

If you want to pass the name of the file to your program at runtime then just add the filename on the command line when you run your program.
c:\myprog.exe file1.txt <Enter>
Then your program can use the arguments to main() to get the filename

 Help with Code Tags 
 C Syntax (Toggle Plain Text) 
int main(int argc, char* argv[])
{
   char* filename = 0;
    if( argc > 1)
        filename = argv[1];
}
int main(int argc, char* argv[])
{
   char* filename = 0;
    if( argc > 1)
        filename = argv[1];
}

Don't PM me with questions -- you might get a nasty PM in response. If you have a question then post it in one of the forums.

•

Join Date: Mar 2006

Posts: 176

Reputation: dubeyprateek is an unknown quantity at this point

Solved Threads: 22

dubeyprateek dubeyprateek is offline

Offline

Junior Poster

Re: Including files at run time

Dec 21st, 2007

Are you talking about including header files at run time ?

Last edited by dubeyprateek; Dec 21st, 2007 at 9:13 am.

I know I am. Therefore I am.

•

Join Date: Oct 2006

Posts: 514

Reputation: Jishnu will become famous soon enough

Solved Threads: 26

Jishnu

Offline

Posting Pro

Re: Including files at run time

Dec 21st, 2007

The files I want to include are header files. They contain definitions of some functions. I want to specify which definitions are to be used at run time.

Last edited by Jishnu; Dec 21st, 2007 at 10:26 am.

•

Join Date: Mar 2006

Posts: 176

Reputation: dubeyprateek is an unknown quantity at this point

Solved Threads: 22

dubeyprateek dubeyprateek is offline

Offline

Junior Poster

Re: Including files at run time

#10

Dec 21st, 2007

You can only have pre processor directives.
#if
#else

You can not include header file as such during runtime.

•

They contain definitions of some functions. I want to specify which definitions are to be used at run time.

Header files normally should contain declarations you are going to use in your application.
If you don't have appropriate declarations you are expecting "undeclared identifier"

There are other ways to include code at runtime like load dlls, but to answer your question you cannot include header file as such on the fly.

I know I am. Therefore I am.