Finds the difference between two times.
doubledifftime(time_ttimer1**,time_ttimer0);**
| Routine | Required Header | Compatibility |
| difftime | <time.h> | ANSI, Win 95, Win NT |
For additional compatibility information, see Compatibility in the Introduction.
Libraries
| LIBC.LIB | Single thread static library, retail version |
| LIBCMT.LIB | Multithread static library, retail version |
| MSVCRT.LIB | Import library for MSVCRT.DLL, retail version |
Return Value
difftime returns the elapsed time in seconds, from timer0 to timer1. The value returned is a double-precision floating-point number.
Parameters
timer1
Ending time
timer0
Beginning time
Remarks
The difftime function computes the difference between the two supplied time values timer0 and timer1.
Example
/* DIFFTIME.C: This program calculates the amount of time
* needed to do a floating-point multiply 10 million times.
*/
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
void main( void )
{
time_t start, finish;
long loop;
double result, elapsed_time;
printf( "Multiplying 2 floating point numbers 10 million times...\n" );
time( &start );
for( loop = 0; loop < 10000000; loop++ )
result = 3.63 * 5.27;
time( &finish );
elapsed_time = difftime( finish, start );
printf( "\nProgram takes %6.0f seconds.\n", elapsed_time );
}
Output
Multiplying 2 floats 10 million times...
Program takes 2 seconds.
Floating-Point Support Routines | Time Management Routines
See Also time