put the code to .h file error gone why?

[key9]

Hi all
I wrote some source code to study,

but I have problem: If I wrote the implement code to .h file directly

code can pass the complie, if I put the code to .cpp file ,it fails , why?

Here's the source code:

[key9@localhost unit]$ gcc -o test test.cpp -lstdc++
/home/key9/tmp/ccgdxJIB.o(.tex t+0x1c2): In function `main':
: undefined reference to `LinuxTestTermi nal::printch(ch ar*)'
/home/key9/tmp/ccgdxJIB.o(.gnu .linkonce.t._ZN 17LinuxTestTerm inalC1Ev+0x19):
In function `LinuxTestTermi nal::LinuxTestT erminal()':
: undefined reference to `vtable for LinuxTestTermin al'
collect2: ld returned 1 exit status

Source code:
********/Terminal.h/*********
#ifndef __TERMINAL_H_
#define __TERMINAL_H_

class Terminal{ // this is virtual class of terminal
public:
virtual void printch(char*) =0;
virtual void backSpace() = 0;
virtual void printCR() = 0;
virtual void printTab() =0;
private:
};
#endif // __TERMINAL_H_
********/LinuxTerminal.h/*********
#ifndef __LINUXTESTTERM INAL_H_
#define __LINUXTESTTERM INAL_H_

#include "Terminal.h "

class LinuxTestTermin al : public Terminal{
public:
void printch(char*);
void backSpace();
void printCR();
void printTab();
};

#endif //__LINUXTESTTERM INAL_H_

********/LinuxTerminal.c pp/*********
#include <stdio.h>
#include "Terminal.h "

void
LinuxTestTermin al::printch(cha r* ch){
printf("%c",*ch );
}
void
LinuxTestTermin al::backSpace() {
printf("/b");
}

void
LinuxTestTermin al::printCR(){
printf("/n");
}
void
LinuxTestTermin al::printTab(){
printf(" ");
}

********/test.cpp/*********
//use -lstdc++

#include <stdio.h>
#include <termios.h>
#include <unistd.h>
#include <iostream>

#include "Terminal.h "
#include "LinuxTerminal. h"

class Terminal;

using namespace std;

int mygetch( ) {
struct termios oldt,newt;
int ch;
tcgetattr( STDIN_FILENO, &oldt );
newt = oldt;
newt.c_lflag &= ~( ICANON | ECHO );
tcsetattr( STDIN_FILENO, TCSANOW, &newt );
ch = getchar();
tcsetattr( STDIN_FILENO, TCSANOW, &oldt );
return ch;
}

int main(int argc, char *argv[])
{

printf("new line of doing test");

LinuxTestTermin al lt;
lt.printch("dsa dadasdasd");

while(mygetch() );

}

*************** *************** ***
another /LinuxTerminal.h/, delete the LinuxTerminal.c pp file
#ifndef __LINUXTESTTERM INAL_H_
#define __LINUXTESTTERM INAL_H_

#include "Terminal.h "

class LinuxTestTermin al : public Terminal{
public:
void printch(char* ch){
printf("%c",*ch );

}
void backSpace(){
printf("/b");

}
void printCR(){
printf("/n");
}
void printTab(){
printf(" ");
}

};

#endif //__LINUXTESTTERM INAL_H_

[Ian Collins]

key9 wrote:

Hi all
I wrote some source code to study,

but I have problem: If I wrote the implement code to .h file directly

code can pass the complie, if I put the code to .cpp file ,it fails , why?

Here's the source code:

[key9@localhost unit]$ gcc -o test test.cpp -lstdc++
/home/key9/tmp/ccgdxJIB.o(.tex t+0x1c2): In function `main':
: undefined reference to `LinuxTestTermi nal::printch(ch ar*)'
/home/key9/tmp/ccgdxJIB.o(.gnu .linkonce.t._ZN 17LinuxTestTerm inalC1Ev+0x19):
In function `LinuxTestTermi nal::LinuxTestT erminal()':
: undefined reference to `vtable for LinuxTestTermin al'
collect2: ld returned 1 exit status

Look like you haven't linked the LinuxTerminal.c pp object file. You
should either compile both cpp files together, or read up on how to link
more than one object file.

--
Ian Collins.

[red floyd]

key9 wrote:

Hi all
I wrote some source code to study,

but I have problem: If I wrote the implement code to .h file directly

code can pass the complie, if I put the code to .cpp file ,it fails , why?

Here's the source code:

[key9@localhost unit]$ gcc -o test test.cpp -lstdc++
/home/key9/tmp/ccgdxJIB.o(.tex t+0x1c2): In function `main':
: undefined reference to `LinuxTestTermi nal::printch(ch ar*)'
/home/key9/tmp/ccgdxJIB.o(.gnu .linkonce.t._ZN 17LinuxTestTerm inalC1Ev+0x19):
In function `LinuxTestTermi nal::LinuxTestT erminal()':
: undefined reference to `vtable for LinuxTestTermin al'
collect2: ld returned 1 exit status

Source code:
********/Terminal.h/*********
#ifndef __TERMINAL_H_
#define __TERMINAL_H_
Irrelevant to your linking problems, but your include guard is invalid
per 17.4.3.1.

[redacted]


********/LinuxTerminal.h/*********
#ifndef __LINUXTESTTERM INAL_H_
#define __LINUXTESTTERM INAL_H_
Same with this include guard.
[redacted]
#ifndef __LINUXTESTTERM INAL_H_
#define __LINUXTESTTERM INAL_H_

And this one.

[redacted]