C/C++ line number

As part of the C++ standard there exists some pre-defined macros that you can use. Section 16.8 of the C++ standard defines amongst other things, the __LINE__ macro.

__LINE__: The line number of the current source line (a decimal constant).
__FILE__: The presumed name of the source file (a character string literal).
__DATE__: The date of translation of the source file (a character string literal...)
__TIME__: The time of translation of the source file (a character string literal...)
__STDC__: Whether__STDC__ is predefined
__cplusplus: The name __cplusplus is defined to the value 199711L when compiling a C ++ translation unit

So your code would be:

if(!Logical)
  printf("Not logical value at line number %d \n",__LINE__);

You should use the preprocessor macro __LINE__ and __FILE__. They are predefined macros and part of the C/C++ standard. During preprocessing, they are replaced respectively by a constant string holding an integer representing the current line number and by the current file name.

Others preprocessor variables :

• __func__ : function name (this is part of C99, not all C++ compilers support it)
• __DATE__ : a string of form "Mmm dd yyyy"
• __TIME__ : a string of form "hh:mm:ss"

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Your code will be :

if(!Logical)
  printf("Not logical value at line number %d in file %s\n", __LINE__, __FILE__);