CODEWITHSUNDEEP
c#batch-fileconsole
rohancragg
rohancragg

Reputation: 5136

Can a Console App know it has been called from a batch file?

Is there a way for a Console app know whether it has been called from a batch file as opposed to directly at the command prompt?

The reason for asking is to find a way to decide whether to initiate a Console.ReadLine loop or similar to await further input, or whether to exit immediately.

Alternatively, is there a way for a batch file to continue sending input to a Console App that is awaiting further input via ReadLine?

Yes, I know - that's 2 questions. If anyone comments that there's an answer to the second question I'll ask that separately.

Upvotes: 0

Views: 369

Answers (4)

jeb
jeb

Reputation: 82267

Possibly your problem is to read only from stdin if there is a redirecton (from your batch file).

This can also be solved (with dotnet) by detecting if there is an input stream.

Solution from @Hans Passant, SO: how to detect if console in stdin has been redirected

using System.Runtime.InteropServices;

public static class ConsoleEx
{
    public static bool OutputRedirected
    {
        get { return FileType.Char != GetFileType(GetStdHandle(StdHandle.Stdout)); }
    }
    public static bool InputRedirected
    {
        get { return FileType.Char != GetFileType(GetStdHandle(StdHandle.Stdin)); }
    }
    public static bool ErrorRedirected
    {
        get { return FileType.Char != GetFileType(GetStdHandle(StdHandle.Stderr)); }
    }

    // P/Invoke:
    private enum FileType { Unknown, Disk, Char, Pipe };
    private enum StdHandle { Stdin = -10, Stdout = -11, Stderr = -12 };
    [DllImport("kernel32.dll")]
    private static extern FileType GetFileType(IntPtr hdl);
    [DllImport("kernel32.dll")]
    private static extern IntPtr GetStdHandle(StdHandle std);
}

And it can be used like this

if (ConsoleEx.InputRedirected)
{
  string strStdin = Console.In.ReadToEnd();
}

Upvotes: 1

ferosekhanj
ferosekhanj

Reputation: 1074

If the batch file knows the input then save the input to a file and feed that to your program like 

prog.exe <argument.txt

in the batch file. I think you need not change the source code for this.

Upvotes: 1

fardjad
fardjad

Reputation: 20394

The batch file can set an environment variable and you can check that in your console application:

in the batch file:

set waitOnDone=0
yourExeFile -arguments

in your Console Application:

var env = System.Environment.GetEnvironmentVariable("waitOnDone");
if (String.IsNullOrEmpty(env) ||  env != "0")
{
    // do something
}

Upvotes: 1

Geoff Appleford
Geoff Appleford

Reputation: 18832

Why not pass in a commandline argument to the console app to determine whether to quit immediately or wait.

Upvotes: 5

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