Thread: Character pointer problem.

This is a problem i am having when i am trying to obtain the address of a character type variable and print the address using cout. the printing works fine when i am using generic pointers by typecasting or if i use printf().

here the second cout statement fails but the fifth is OK.

Strange....

Code:

#include<iostream.h>

int main()
{
	void *gp1,*gp2,*gp3;
	int *ip,i;
	char *cp,c;
	float *fp,f;

	i=10;
	c='a';
	f=11.11;

	ip=&i;
	cp=&c;
	fp=&f;

	gp1=ip;
	gp2=cp;
	gp3=fp;

	cout<<endl<<"# IP:-- Integer is "<<*ip<<" at address "<<ip<<endl;
	cout<<"# CP:-- Character is "<<*cp<<" at address "<<cp<<endl;
	cout<<"# FP:-- Float is "<<*fp<<" at address "<<fp<<endl;

	cout<<"# GP1:-- Integer is "<<*(int*)gp1<<" at address "<<gp1<<endl;
	cout<<"# GP2:-- Character is "<<*(char*)gp2<<" at address "<<gp2<<endl;
	cout<<"# GP3:-- Float is "<<*(float*)gp3<<" at address "<<gp3<<endl;

	*ip=c;
	*cp=f;
	*fp=i;

	cout<<endl<<"Now pointing to char by int pointer and vice versa..."<<endl;
	cout<<endl;

	cout<<"# IP:-- Integer is "<<*(char*)ip<<" at address "<<ip<<endl;
	cout<<"# CP:-- Character is "<<*(float*)cp<<" at address "<<cp<<endl;
	cout<<"# FP:-- Float is "<<*(int*)fp<<" at address "<<fp<<endl;

	return 0;
}

I am using Turbo C++ 3.0 and Borland C++ 5.0 compilers...

int main(int argc, char* argv[])
{
void *gp1,*gp2,*gp3;
int *ip,i;
char *cp,c;
float *fp,f;

i=10;
c='a';
f=11.11;

ip=&i;
cp=&c;
fp=&f;

gp1=ip;
gp2=cp;
gp3=fp;

cout<<endl<<"# IP:-- Integer is "<<*ip<<" at address "<<ip<<endl;
cout<<"# CP:-- Character is "<<*cp<<" at address "<<cp<<endl;

//operator<< of object cout automatically interprets the pointer cp (of type char*) as a character array,
//because it accepts strings by default.
//this is why you can type the following simple statement:
//cout<<"Example";
//The string "Example" is an array of characters too.
//You also see al lot of strange looking characters after the 'a' value.
//the operator<< of cout looks for an end of string '\0' character.
//And this is not immediatly found after the character 'a'.

cout<<"# FP:-- Float is "<<*fp<<" at address "<<fp<<endl;

cout<<"# GP1:-- Integer is "<<*(int*)gp1<<" at address "<<gp1<<endl;
cout<<"# GP2:-- Character is "<<*(char*)gp2<<" at address "<<gp2<<endl;

//the above explanation explains why this statements works as desired.
//since the operator<< of cout does not recognize the type of gp2 as a char*,
//it prints the value of the pointer.

cout<<"# GP3:-- Float is "<<*(float*)gp3<<" at address "<<gp3<<endl;

*ip=c;
*cp=f;
*fp=i;

cout<<endl<<"Now pointing to char by int pointer and vice versa..."<<endl;
cout<<endl;

cout<<"# IP:-- Integer is "<<*(char*)ip<<" at address "<<ip<<endl;
cout<<"# CP:-- Character is "<<*(float*)cp<<" at address "<<cp<<endl;

//here you have the same interpretion as in the first explanation.

cout<<"# FP:-- Float is "<<*(int*)fp<<" at address "<<fp<<endl;

return 0;


}