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Checking an array for NULL in C++

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# 1  
Old 08-02-2011
Checking an array for NULL in C++
Hello All,

I have this question that how to check for an array for NULL?

HTML Code:
For eg. 
 
#include<iostream.h>
using namespace std;
 
int main()
{
      char arr[10];
      if(arr == NULL)
      {
            cout<<"NULL";
       }
}
Thanks a lott in advance!!!
# 2  
Old 08-02-2011
Include <stdio.h> and that'll work actually. But why would you check if an array's null? It can't be null. If it was a pointer, it might end up as NULL through a mistake.

I might just not understand what you're trying to do, though.
Last edited by Corona688; 08-02-2011 at 02:07 PM..
# 3  
Old 08-02-2011
Actually ...wt. I had to check was that if the char pointer has a string initialized or it is not yet initialized.

But I am checking it by doing (strcmp(arr, "")== 0) instead of (arr== NULL), latter which is not correct for the reason you mentioned above!!!!!

Thanks though SmilieSmilie
# 4  
Old 08-02-2011
Quote:
Originally Posted by mind@work
Actually ...wt. I had to check was that if the char pointer has a string initialized or it is not yet initialized.
To check if a string is zero length is easy even without a function call.
Code:
if(str[0] == '\0')

But uninitialized doesn't mean zero length, uninitialized means undefined. That means empty only if you're lucky. If you're unlucky it could be full of garbage. Don't check if a string is uninitialized -- don't leave around uninitialized strings, period.
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