C++ Save console output to a text file before quit WINAPI ( No MFC )

Question

I am trying to get my program to log the output of a console application to a text file before it quits. This is a GUI program which launches the console application (tool.exe). The problem is that I am using CTRL + C to quit the console application. This console application cant be altered either. I have tried a few ways of doing this but none have seemed to work ( tool.exe > output.txt ).

Can anyone point me in the right direction of which approach to take ? It would be greatly appreciated.

EDIT:

The file is created but it is empty and does not receive any data. The thing I am after noticing though is if I run the tool from the command line myself, it will work. Eg. c:\\>tool.exe > output.txt However this is not working when its executed from my GUI application.

Here is the code I am using to execute the tool:

    strcpy (tool, "\" start /D \"");
    strcat (tool, toolLocation);
    strcat (tool, "\" tool.exe > output.txt\"");
    system (tool);

This will run tool.exe and create output.txt fine but will not output anything to the file.

EDIT2:

I think what is actually happening is that because I am using start , the >output.txt is outputing start instead of tool.exe . This would explain why it creates the empty file. Start is just running a fresh command line which is then running tool.exe . The problem is, how do I get around this issue now ?

Answer 1

Try:

#include <signal.h>
void signal_handlerkill(int sig)
{
  //Do Soemthing
  exit(1);
}

int main()
{
  signal(SIGINT, signal_handlerkill); //Connect the interrupt signal (^C) to the function
  //Do your code here
  return 0;
}

And if that doesn't work, I'd suggest looking here . Specifically:

// crt_signal.c
// compile with: /c
// Use signal to attach a signal handler to the abort routine
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <tchar.h>

void SignalHandler(int signal)
{
    printf("Application aborting...\n");
}

int main()
{
    typedef void (*SignalHandlerPointer)(int);

    SignalHandlerPointer previousHandler;
    previousHandler = signal(SIGABRT, SignalHandler);

    abort();
}

Answer 2

If you run the application without redirecting to a file, do you see the output you need on the console when you press ctrl+c?

If you don't then there is nothing you can do since you cannot change the application.

Update

What you need is to redirect stdout and stderr to the file. I have never done that but jamesdlin seems to have done that. Take a look at his comment.

What you could try is instead of using start try using cmd.exe directly.

Answer 3

This is the code which managed to solve the problem for me:

            char path[500]; //Create character array
            strcpy (path, "cd "); //Copy 'cd' into the array
            strcat (path, toolLocation); //Copy the path of the tool into the array
            strcat (path, " & ip.exe > output.txt"); //Append on the name of the exe and output to a file
            system (path); //Run the built array

I am creating a character array and then appending to it. The vital bit here was the & being used in the system call. This is working as an and and first cd'ing to the firectory before executing the .exe.