Turning C output into C# input

Question

I am currently trying to develop a program which takes the output of an existing program (written in C) and uses it as input (in C#). The problem I am having is that the existing program prints data in redundant format but it dynamically changes. An example could be a random name generator and I need to make a program that logs all of the random names as they appear.

Could I just pipe this and the output will be grabbed as it comes? The C program is run from a CLI.

Answer 1

You could redirect the output streams from the Process object to get direct access to it. You make a call and it will invoke an event of your choice when output is received. One of my questions may provide some explanation on how to do this - C# Shell - IO redirection:

processObject.StartInfo.RedirectStandardOutput = true;
processObject.OutputDataReceived += new DataReceivedEventHandler(processObject_OutputDataReceived);
/* ... */
processObject.Start();
processObject.BeginOutputReadLine();

And then later:

public void processObject_OutputDataReceived(object sender, DataReceivedEventArgs e) {
    ProcessNewData(e.Data);
}

Note that this includes the trailing newline.

Or you can just pipe it and use Console.ReadLine to read it in. On the command line, you would execute:

cprogram | csharp_program

Unfortunately, you can't do this directly with the Process object - just use the method above. If you do choose to go this route, you can use:

string input = "";
int currentChar = 0;

while ( (currentChar = Console.Read()) > -1 ) {
    input += Convert.ToChar(currentChar);
}

Which will read from the input until EOF.

Answer 2

If the C# program is also command-line based, running this command from the command-line will chain them together:

my_c_program.exe | my_csharp_program.exe

The C# program will receive the output of the C program, via its standard input stream (Console.Read, etc.)