update executable file

Hi All,
Is it possible to update an executable file created using cc or gcc compiler.
ie., very clearly
If i create a C program and execute it and an executable file a.out is created.
but the run time for the execution is around 30 minutes.
Is it possible to update that executable, if some small changes had been made to source code.
since the compiler takes 30 min. again to get the updated result.

I am not an expert in C. but this seems, hitting my mind for a long time...
Is there any way to achieve this or this is an Impossible task.

Thanks in Advance,
Anent

You cannot overwrite a running executable.
You will trash the running program.

You could compile your C code...
gcc myfile.c

...then...
mv a.out newprog

...then run...
newprog

...then edit and compile your C code...
gcc myfile.c

...a.out will be created without trashing
the running program.

Try this:

gcc source.c -o ProgramName

I use this command in Sun OS without any problem.

Thanks rwb & MacMonster,
I want to clear out a little bit.
I have my executable file ready. and if i make changes in the source code and again if i compile the code. it takes the same time for compiling.

what i need is : the already available executable should be updated without overwriting with the executable created with the same name.

ie.,
gcc test.c -o myprog
o/p : myprog - executable file
if i run it again, - after small modification
gcc test.c -o myprog
o/p : myprog - exe file - but same compiling time.
but the modification made to the source is a little bit.

Idea:
Case 1; If i create some modules of C source codes.and if i modify the code to any one of the module.
How can i reduce my runtime of the exe file creation.
Case 2; If it is a single module.. then.

any inputs are appreciated.
Anent