[Mono-bugs] [Bug 43741][Wis] New - System.IO.StreamReader.Peek confuses end-of-line and end-of-file

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Changed by tonyg@lshift.net.

http://bugzilla.ximian.com/show_bug.cgi?id=43741

--- shadow/43741	Tue May 27 13:42:07 2003
+++ shadow/43741.tmp.6345	Tue May 27 13:42:07 2003
@@ -0,0 +1,91 @@
+Bug#: 43741
+Product: Mono/Class Libraries
+Version: unspecified
+OS: All
+OS Details: RH linux 7.2, Windows XP sp1
+Status: NEW   
+Resolution: 
+Severity: 
+Priority: Wishlist
+Component: CORLIB
+AssignedTo: mono-bugs@ximian.com                            
+ReportedBy: tonyg@lshift.net               
+QAContact: mono-bugs@ximian.com
+TargetMilestone: ---
+URL: 
+Cc: 
+Summary: System.IO.StreamReader.Peek confuses end-of-line and end-of-file
+
+This code snippet, involving System.IO.TextReader.Peek (really
+StreamReader.Peek) appears to me to confuse end-of-line (actually,
+end-of-currently-available-input) with end-of-file when reading from
+System.Console.In (or any StreamReader?).
+
+This happens on both Mono 0.24 on Linux and MS .NET 1.1 on Windows XP.
+
+I'm trying to see if the stream is finished *without* advancing the stream
+position.
+
+1. am I using the API wrong? I hope so.
+2. if not, is this a bug in the implementation, or in the spec? or
+   is there a hole in the spec?
+
+Here's the output I get, when I type 123<ret> at it:
+
+	Peeking: 49
+	Reading: 49
+	read: 49 (1)
+	Peeking: 50
+	Reading: 50
+	read: 50 (2)
+	Peeking: 51
+	Reading: 51
+	read: 51 (3)
+	Peeking: 10
+	Reading: 10
+	read: 10 (
+	)
+	Peeking: -1
+	bye!
+
+(MS.NET on Windows is the same, except you get a 13 before the 10)
+
+I would expect it to block, waiting for the first char of the next line of
+input after the linefeed char was returned; instead it reports something
+operationally indistinguishable from end-of-file as soon as it sees the end
+of the first line.
+
+Here's the code:
+
+	using System;
+	using System.IO;
+	using System.Text;
+
+	public class rtcs2 {
+	    public static void Main(String[] args) {
+		while (true) {
+		    int ch = P();
+		    if (ch == -1) {
+			// No more characters available.
+			// End of file?
+			System.Console.WriteLine("bye!");
+			break;
+		    }
+		    ch = R();
+		    System.Console.WriteLine("read: "+
+			ch+" ("+((char)ch)+")");
+		}
+	    }
+
+	    private static int P() {
+		int r = System.Console.In.Peek();
+		System.Console.WriteLine("Peeking: "+r);
+		return r;
+	    }
+
+	    private static int R() {
+		int r = System.Console.In.Read();
+		System.Console.WriteLine("Reading: "+r);
+		return r;
+	    }
+	}