//-------------------------------------------------------------------
//	myrusage.cpp
//
//	This program demonstrates use of the 'getrusage()' function
//	as it is currently implemented under Linux (kernel 2.6.26).
//
//		to compile:  $ g++ myrusage.cpp -o myrusage
//		to execute:  $ ./myrusage
//
//	programmer: ALLAN CRUSE
//	written on: 09 MAR 2009
//-------------------------------------------------------------------

#include <stdio.h>		// for printf(), perror() 
#include <unistd.h>		// for fork()  
#include <stdlib.h>		// for exit() 
#include <sys/wait.h>		// for wait()
#include <sys/resource.h>	// for getrusage()

int main( int argc, char **argv )
{
	if ( fork() == 0 )
		{
		printf( " Child-process will sleep\n" );
		sleep(1);
		printf( " Child-process is exiting\n" );
		exit(0);
		}

	wait( NULL );

	struct rusage	myrusage = { 0 };

	if ( getrusage( RUSAGE_SELF, &myrusage ) < 0 ) 
		{ perror( "rusage" ); exit(1); }

	printf( "\n Current resource usages: \n" );	

	printf( "\n\t  user time consumed: " );
	printf( "%lu seconds ", myrusage.ru_utime.tv_sec );
	printf( "%lu microseconds ", myrusage.ru_utime.tv_usec );

	printf( "\n\tsystem time consumed: " );
	printf( "%lu seconds ", myrusage.ru_stime.tv_sec );
	printf( "%lu microseconds \n", myrusage.ru_stime.tv_usec );


	printf( "\n\tpage reclaims: %lu ", myrusage.ru_minflt );
	printf( "\tvoluntary context switches: %lu ", myrusage.ru_nvcsw );
	printf( "\n\tpage faults: %lu \t", myrusage.ru_majflt );
	printf( "\tinvoluntary context switches: %lu\n", myrusage.ru_nivcsw );


	int	len = sizeof( myrusage );
	printf( "\n sizeof( myrusage ) = %d bytes ", len );
	int	n = sizeof( myrusage ) / sizeof( long );
	unsigned long	*lp = (unsigned long*)&myrusage;
	for (int i = 0; i < n; i++)
		{
		if ( (i % 4) == 0 ) printf( "\n " );
		printf( "%016X ", lp[i] );
		}
	printf( "\n\n" );

 

	
}