Problem the Strings in C++
 

Hi guys,

i wrote one simple program in C++ as follows,

#include<iostream.h>
#include<string.h>
main()
{
char *temp="How are you";
char *ret="";
strcpy(ret,temp);
cout<<temp;
}

It is running in windows fine.
But with linux, it gives "Segmentation Fault (core dumped)" Error.
But it compiles with no error.

If i change the destination variable in strcpy to fixed array size like
char ret[100];

it works fine in linux.

why linux is not accepting the destination as pointer char.

thanx in advance
Jagadish

The question should be, "Why is Windows accepting running this buggy code ?"
No surprise so many viruses are happy in the Windows ecosystem !

Hi,

Can u explain me what is wrong with that code.

Can't we use the char pointer as destination in strcpy.

thanx for ur reply
Jagadish

The problem is that the character array at "ret" is not large enough (only 1 char) to hold the null-terminated string "How are you" (12 chars) and you're writing past the end of the array into other parts of memory.

You can use a char pointer as destination, but it need to point to some memory you are allowed to write to and with sufficient storage.
This pointer is initialized in your code to a one byte array that may or may not be writable, depending of the compiler implementation/options, the strcpy is also trashing some part of your windows stack as you are overwriting whatever is after this one byte array with the remaining of your source string.