C6303

Note

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warning C6303: format string mismatch: wide character string passed as parameter <number> when character string is required in call to <function>

This warning indicates that the format string specifies that a character string is required. However, a wide character string is being passed. This defect is likely to cause a crash or corruption of some form.

Example

The following sample code generates this warning:

#include <stdio.h>  
  
void f()  
{  
  wchar_t buff[5] = L"hi";  
  
  printf("%s", buff);  
}  

To correct this warning, use %ls as shown in the following sample code:

#include <stdio.h>  
  
void f()  
{  
  wchar_t buff[5] = L"hi";  
  
  printf("%ls", buff);  
}  

The following sample code uses safe string manipulation function printf_s to correct this warning:

#include <stdio.h>  
  
void f()  
{  
  wchar_t buff[5] = L"hi";  
  
  printf_s("%ls",buff);  
}