Predefined Macros

Macro Description
__DATE__ The current date as a character literal in "MMM DD YYYY" format
__TIME__ The current time as a character literal in "HH:MM:SS" format
__FILE__ This contains the current filename as a string literal.
__LINE__ This contains the current line number as a decimal constant.
__STDC__ Defined as 1 when the compiler complies with the ANSI standard.

e.g.:

#include 

main()
{
   printf("File :%s \n", __FILE__ );
   printf("Date :%s \n", __DATE__ );
   printf("Time :%s \n", __TIME__ );
   printf("Line :%d \n", __LINE__ );
   printf("ANSI :%d \n", __STDC__ );

}

Compile & run:

File :test.c 

Date :Jun 2 2012
Time :03:36:24
Line :8
ANSI :1

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