ANSI C CPP symbols and program to demonstrate it

ANSI C CPP symbols and program to demonstrate it

Answer

ANSI C defines a set of C processor(CPP) symbols, which may be used in user programs. These symbols are assigned actual values at compilation time.

cpp SYMBOL	USE
_STDC_	Feature test macro. Value is 1 if a compiler is ANSI C, 0 otherwise
_LINE_	Evaluated to the physical line number of a source file.
_FILE_	Value is the file name of a module that contains this symbol.
_DATE_	Value is the date that a module containing this symbol is compiled.
_TIME_	value is the time that a module containing this symbol is compiled.

test_ansi_c.c program illustrates the use of the above symbols:
#include<stdio.h> int main() {    #if _STDC_==0      printf(“cc is not ANSI C compliant”);    #else      printf(“%s compiled at %s:%s.               This statement is at line %d\n”,               _FILE_ , _DATE_ , _TIME_ , _LINE_ );    #endif                Return 0; }