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error passing 'const Filesys'

cory244 (43)
I am getting an error line 5 of filesys about passing 'const Filesys' as 'this' argument of std:string Sdrive I am not able to see why looks like it is passing correctly to me. Any help would be greatly appreciated.

Filesys class
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#ifndef FILESYS_H
#define FILESYS_H

#include<iostream>
#include<string>
#include<fstream>
#include<sstream>
#include<vector>
//#include"Shell.h"
#include"Sdrive.h"

using namespace std;
class Filesys: public Sdrive
{

	private:
	int rootsize;					//maximum number of entries in ROOT
	int fatsize;					//number of blocks occupied by FAT
	vector<string> filenames;		// filenames in root
	vector<int>	firstblock;		// firstblocks in ROOT
	vector<int>	fat;			// File Allocation Table

	public:
	Filesys( string filename); //creates an Sdrive
	int fsclose();	//
	int fssyncout (); //
	void buildfilenames(); //
	void buildfat(); //


	int newfile (string file); //
	int rmfile (string file);//
	int getfirstblock(string file);//

	int addblock (string file , string block);//
	int delblock(string file , int blocknumber);
	int readblock(string file , int blocknumber,string buffer);

	int writeblock (string file , int blocknumber , string buffer);
	int nextblock(string file , int blocknumber) ;
	int getrootsize(); //

	int getfatsize(); //
	int getblocksize()const; //
	string getdiskname() const; //

	bool fileinroot(string file);//
	vector<string> block(string s , int i);//
	bool blockinfile(string s, int i);//

	void display();
};
 string Filesys::getdiskname() const
{
	string temp = Sdrive::getname();
	return temp;
}


Sdrive Class
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class Sdrive {
public:
	//Sdrive  ( string diskname );
	Sdrive ( string diskname , int numberofblocks , int blocksize );
	int getblock( int blocknumber , string& buffer);
	int putblock( int blocknumber , string buffer);
	string getname() {return diskname;}
	int getblocksize() { return blocksize;}
private:
	string diskname; 		//file name of software disk
	int numberofblocks;		//number of blocks on disk
	int blocksize;			//block size in bytes
};
Peter87 (11238)
You are not allowed to call a non-const member function from a const member function. You probably want Sdrive::getname() to be const.
cory244 (43)
Ah gotcha, thank you but I am still getting an error in that section lines 56 says no matching function for call to Sdrive::Sdrive(std::string&)? I appreciate it.
YokoTsuno (60)
I can't see that call in the above code, but I presume you do not have an overloaded constructor that only takes in a string as parameter. Post your new code.
cory244 (43)
I am getting my error here
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Filesys::Filesys( string filename) : Sdrive( filename)
{
//some code

}


Thank you in advanced, when I change it from Sdrive(filename) to Sdrive(getname)

Throws the error: no matching function call to Sdrive::Sdrive (<unresolved overloaded function type>)'
Zhuge (4664)
getname is the name of a function. Did you mean to actually call the function? I think you really do want filename there though, as calling Sdrive's method won't be useful since it hasn't even been constructed yet.
YokoTsuno (60)
Like I said somehow Sdrive does not have: Sdrive::Sdrive(string filename). Check "Sdrive.h"
Zhuge (4664)
Looking at the OP, it seems to be commented out on line 3. TC, I suggest you check the header file that defines Sdrive as suggested.
cory244 (43)
Awesome thanks guys think I got it figured out now. Sorry so late on reply been busy week just now got to test this out, thank you to all of you.
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