Advanced Programming in the UNIX® Environment

ptg10805159

938 Solutions to Selected Exercises Appendix C

Instead, when a linked list is built in a shared memory segment, the list pointers

should be stored as offsets to other objects in the shared memory segment. These

offsets areformed by subtracting the start of the shared memory segment from

the actual address of the object.

15.14 FigureC.21 shows the relevant events.

Parenti Childi Shared value update

set to set to set to returns Comment

0initialized bymmap

1child runs first, then is blocked

0parent runs

1

0then parent is blocked

2child resumes

1

3then child is blocked

2parent resumes

3

2then parent is blocked

4

3

5then child is blocked

4parent resumes

Figure C.21 Alternation between parent and child in Figure15.33

Chapter 16

16.1 FigureC.22 shows a program that prints the system’s byte order.

#include <stdio.h>

#include <stdlib.h>

#include <inttypes.h>

int

main(void)

{

uint32_t i=0x04030201;

unsigned char *cp = (unsigned char *)&i;

if (*cp == 1)

printf("little-endian\n");

else if (*cp == 4)

printf("big-endian\n");

else

printf("who knows?\n");

exit(0);

}

Figure C.22 Determine byte order on system