参考答案

void main( void )

　　{

　　String str("zhanglin");

　　_onexit( fn1 );

　　_onexit( fn2 );

　　_onexit( fn3 );

　　_onexit( fn4 );

　　printf( "This is executed first.\n" );

　　}

　　int fn1()

　　{

　　printf( "next.\n" );

　　return 0;

　　}

　　int fn2()

　　{

　　printf( "executed " );

　　return 0;

　　}

　　int fn3()

　　{

　　printf( "is " );

　　return 0;

　　}

　　int fn4()

　　{

　　printf( "This " );

　　return 0;

　　}

　　The _onexit function is passed the address of a function (func) to be called when the program terminates normally. Successive calls to _onexit create a register of functions that are executed in LIFO (last-in-first-out) order. The functions passed to _onexit cannot take parameters.