Advanced Programming in the UNIX® Environment

ptg10805159 Section 15.8 Semaphores 567 Typical values FreeBSD Linux Mac OS X Solaris 8.0 3.2.0 10.6.8 10 Description maximum va ...

ptg10805159 568 Interprocess Communication Chapter 15 Note that the optional argument is the actual union, not a pointer to the ...

ptg10805159 Section 15.8 Semaphores 569 struct sembuf { unsigned short sem_num; /* member # in set (0, 1, ..., nsems-1) */ short ...

ptg10805159 570 Interprocess Communication Chapter 15 If the semaphore’s value is currently 0, the function returns immediately. ...

ptg10805159 Section 15.9 Shared Memory 571 byte; to release it, we unlock the byte. The recordlocking properties guarantee that ...

ptg10805159 572 Interprocess Communication Chapter 15 The Single UNIX Specification shared memory objects option includes altern ...

ptg10805159 Section 15.9 Shared Memory 573 shm_lpid,shm_nattch,shm_atime,andshm_dtimeareall set to 0. shm_ctimeis set to the cu ...

ptg10805159 574 Interprocess Communication Chapter 15 Once a shared memory segment has been created, a process attaches it to it ...

ptg10805159 Section 15.9 Shared Memory 575 #include "apue.h" #include <sys/shm.h> #define ARRAY_SIZE 40000 #define MALLOC_ ...

ptg10805159 576 Interprocess Communication Chapter 15 stack shared memory heap uninitialized data (bss) initialized data text co ...

ptg10805159 Section 15.9 Shared Memory 577 #include "apue.h" #include <fcntl.h> #include <sys/mman.h> #define NLOOPS ...

ptg10805159 578 Interprocess Communication Chapter 15 The program opens the/dev/zerodevice and callsmmap,specifying a size of a ...

ptg10805159 Section 15.10 POSIX Semaphores 579 15.10 POSIX Semaphores The POSIX semaphoremechanism is one of three IPC mechanism ...

ptg10805159 580 Interprocess Communication Chapter 15 creation mask (Sections 4.5 and 4.8). Note, however,that only read and wri ...

ptg10805159 Section 15.10 POSIX Semaphores 581 Thesem_unlinkfunction removes the name of the semaphore. If thereare noopen refer ...

ptg10805159 582 Interprocess Communication Chapter 15 #include <semaphore.h> int sem_post(sem_t *sem); Returns: 0 if OK,−1 ...

ptg10805159 Section 15.10 POSIX Semaphores 583 Example One of the motivations for introducing the POSIX semaphoreinterfaces was ...

ptg10805159 584 Interprocess Communication Chapter 15 s_alloc() { struct slock *sp; static int cnt; if ((sp = malloc(sizeof(stru ...

ptg10805159 Section 15.11Client–Server Properties 585 15.11 Client–ServerProper ties Let’s detail some of the properties of clie ...

ptg10805159 586 Interprocess Communication Chapter 15 with a key ofIPC_PRIVATE.The server also has its own queue, with a key or ...