[kemnet]

Hello.
Question.

Lets say I write an executable program that is supposed to do

A+B+C

but i made a mistake and it does
A+B-C

and i only discovered this error after i built the program and sold it so someone.
how do i write a separate executable / patch i can send to the person that will correct that error IN c++.
Thank YOU

[virxen]

send him the executable file to overwrite the wrong one

[kemnet]

well yes...but...im thinking if its a big program. Cant I just write up a little code that will do that?instead of the WHOleeeee Executable?

[virxen]

then try the patch method

read both files and find the differences(what the difference is and where)
write the data in a file
and send this with an exe patcher program to issue the changes to the old program

[kemnet]

ok with this patch method if you have four forms will you be able to specify that you only want to check out the code on the 1st form?

[seomanju]

thanks

[kemnet]

Quote:

Originally Posted by seomanju

thanks

what for

[virxen]

Quote:

Originally Posted by kemnet

ok with this patch method if you have four forms will you be able to specify that you only want to check out the code on the 1st form?

you check only the executable file

[kemnet]

ok so i must redo the whole executable?

[virxen]

this is patch1.cpp

#include <stdio.h>

int main(){
    int A=1,B=2,C=0;
    C=A+B;
    printf("\nC=%d",C);
    getchar();
    return 0;
}

this patch2.cpp

#include <stdio.h>

int main(){
    int A=1,B=2,C=0;
    C=A-B;
    printf("\nC=%d",C);
    getchar();
    return 0;
}

patch2.cpp is the program with the error and patch1.cpp is the correct one

you compile both of them

if you see the executables in a hex editor and compare them with each other
you will see that most of the files are the same.
you need to change only the differences

in dos prompt you can use fc=filecompare like this
fc patch1.exe patch2.exe >differences.txt

in this text file you will see what you have to change in patch2.exe in order to become patch1.exe

see the files in the zip file.


p.s. all the above must be done programatically by you
or you can use something like this to do it automatically http://sourceforge.net/projects/jojodiff/



also another article based on what you want is here http://www.codediesel.com/tools/tran...files-quickly/