How to reroute a system call output to local variable in C++?

[Weegee]

Hello,

For example, I can do this call to get the output to a text file:

system("dir > temp.txt");

But does anyone know how to get the output to a local variable like CString or char*?

Thanks in advanced.
-weeg

[Laharl]

You mean other than opening temp.txt and reading its contents using C++?

[Weegee]

Yep. I'd like to skip the i/o step, and process the string directly...that is if it's possible.

[weaknessforcats]

Just use printf or cout on your CString and redirect yout program output to a text file.

CString means you are probably using Visual Studio.NET and that means you go to your project properties for Debugging and put in your command line arguments like >testout.txt. You don't use the program name as a command line argument.

[oler1s]

Look at the idea of pipes. And piping streams. A UNIX function that's a good search term for the entire topic is popen. Try those, and read about it. Windows can execute a process, and pipe output of the spawned process to your program. Look around, and you'll find out how.

[RRick]

The problem you have is with the system command. It will run a command for you, but the only return value from system is the return code from the command string. System redirects all output to STDOUT, and I don't know of any way to easily catch that info.

Also, I don't know any other C/C++ command you can use. Other languages (like bash and perl) have mechanisms to collect output, but C/C++ seems to be missing these mechanisms.

[arnaudk]

If all you want to do is get a directory listing, you might check out boost::filesyst em, or have a look through windows file management on msdn.

[Weegee]

Thanks everyone for giving me some suggestions! :) I went ahead and searched around and found CreateProcess() . It's a little involved, but I finally got it working for what I needed to do.

Thanks again!
-weeg