unusual fstream problems

For some reason, a bunch of functions won't compile using fstreams- most importantly, seekg and seekp:

Error : 'seekg' is not a struct/union/class member
readertest.cp line 41 readMe.seekg(1);

I have the fstream and iostream headers included. I've even downloaded example code that worked for other people, but still the same error.

Is there some reason why such functions would not be recognized? Any suggestions/ideas would be appreciated.

Thanks!

(BTW, I'm running an old version of Metrowerks Codewarrior IDE on Macintosh.)

Well if it's code that's worked before I've no idea. But if you have declared readme as a pointer you'd want:

Code:

---

readMe->seekg(1).

---

dt

Could you post some code? It's kind of hard to tell if anything's wrong if you can't see the code ;)

Well, the code is really only that one statement. But here goes.

btw, I'm not sure how to paste in code the correct way, so sorry if it's messy.

// Headers

#include <iostream.h>
#include <fstream.h>
#include <stdio.h>
#include <stdlib.h>


// Proto

int load(int loc);


// Main

int main()
{

load(1);

return 0;
}


// Load
int load(int loc=1)
{
ifstream readMe( "data file" );
char buff;
int count=1;
int isFound=0;
int length;


readMe.seekg(1);
readMe.get(buff);
cout << buff;
cout << length;

return 1;

} // end load

If you want to post code, use [code ] and [/code ] tags, but without the spaces.

Potential problem: The file begins at 0, not 1.
Problem: length is never initialized
Potential problem: If the file is of length 1 or 0, buff will contain a garbage value because you will hit eof() when reading from position 1.

Problem: You're using old-style headers (iostream.h, etc. instead of <iostream>, <fstream>)
Problem: The C headers (stdio.h, stdlib.h) should be replaced with <cstdio>, <cstdlib>

Good to see you're not using void main() though :)

regarding problem 1- the point of using seekg() was to start somewhere besides the beginning of the file. hence (1) and not (0).

problem 2- I'm not using length any more; the program is only supposed to read 1 char now.

problem 3- the data files I'm reading from are never of small length. but, when I actually start writing the program I will of course address that.

problem 4- true enough

problem 5- doesn't seem to work with my compiler.

Minor issues aside, I still can't use the seek commands at all. Any ideas about that? Might I need a new <fstream> header file?

Oh right, forgot... you're getting syntax errors, not logic errors.. lol!

Are you getting any errors before this? If not, try creating a new project instead... and if that doesn't work, reinstall your compiler... and if that doesn't work, try re-downloading then reinstalling your compiler... and if that doesn't work, borrow a friend's compiler... and if that doesn't work, reinstall your OS... and then throw your computer out the window ;)

unfortunately it happens with all projects.

however, in the mean time I created a simple structure to replace seek:

[code] while (count<loc-1)
{
readMe.get();
count++;
}
readMe.get(buff);
cout << buff; [/uncode]

a bit inelegant, but it works.

Quote:

---

Originally Posted by georgefoxjunior

Well, the code is really only that one statement. But here goes.

btw, I'm not sure how to paste in code the correct way, so sorry if it's messy.

Code:

---

// Headers

#include <iostream.h>
#include <fstream.h>
#include <stdio.h>
#include <stdlib.h>


// Proto

int load(int loc);


// Main

int        main()
{
       
        load(1);
       
        return 0;
}


// Load
int load(int loc=1)
{
        ifstream        readMe( "data file" );
        char                buff;
        int                        count=1;
        int                        isFound=0;       
        int                        length;       
       
       
        readMe.seekg(1);
        readMe.get(buff);
        cout << buff;
        cout << length;
       
        return 1;
       
} // end load

---

---

(I added code tags)

Well, regardless of program quality and program bugs, this appears to me to be a syntactically valid C++ program. How are you compiling it? If you try to compile it as a C program you may get errors about seekg and lots of other things. (Don't have any way to test it with CodeWarrier.)

Regards,

Dave

^ what he said.

>>readertest.cp
If that's .cp and not .cpp, it's possible that it's compiling as a C program (although the C extension is .c). Rename it to .cpp, then check your options and stuff to make sure you're compiling as a C++ program.

running result is '7798112', what's mean this ?

this is edited code:

Code:

---

#include <iostream>
#include <fstream>
#include <stdio.h>
#include <stdlib.h>

using namespace std;  //add this is ok

int load(int loc);

int main()
{
    load(1);

    cin.ignore();              //add this to stop closing window
    cin.get();
    return 0;
}

int load(int loc=1)
{
    ifstream readMe( "data file" );
    char buff;
    int count=1;
    int isFound=0;
    int length;


    readMe.seekg(1);
    readMe.get(buff);
    cout << buff;
    cout << length;

    return 1;

}

---

length could be anything; after declaring it, you never use it. It's still set to an uninitalized value. You never use count, either.