Noob questions

[Erinaceus]

In case you have not solved the 3rd problem yet (your code is 
almost there),
it can be fixed by replacing this line:
	rawfile.écrire(uncompress(efile_buf2)); // alias for 
std.file.write
with this one:
	(filename ~ ".out").écrire(uncompress(efile_buf2));

The lines that open files using std.stdio.File are not needed and 
can be removed:
	File efile = File(filename, "r");
	File rawfile = File(filename ~ ".out", "w");

std.file.write works pretty much like this:
	void write(string filename, void[] writeThis) {
		import std.stdio;
		File f = File(filename, "w");
		f.rawWrite(writeThis);
		f.close();
	}

It expects a filename as an argument (not a std.stdio.File 
structure representing an open file). std.file.read also expects 
a filename, your code is calling that one correctly.
Using std.stdio.File is not necessary here because 
std.file.read/write open and close the files on their own.


About your 2nd problem: its hard to tell whats going on without 
more complete code. You may want to inspect the problematic 
string using something like this:
	string correct = "test.txt";
	string tricky = std.string.strip(readln());
	writeln("c: ", cast(ubyte[]) correct);
	writeln("t: ", cast(ubyte[]) tricky);

This is going to print numeric codes of all bytes in the string 
and reveal any potentially invisible characters (like spaces, 
line-ending markers, tabs etc.), like this:
	c: [116, 101, 115, 116, 46, 116, 120, 116]
	t: [116, 101, 115, 116, 46, 116, 120, 116, 13]