读书时间 05/28/2011 -2

《Linux编程技术详解》 杜华 -- 续

1. 带日志的Daemon

int main(int argc, char **argv) {

int i=0;

daemon(0,0);

openlog(argv[0], LOG_CONS | LOG_PID, LOG_USER);

for(i=0;i<100;i++) {

sleep(1);

syslog(LOG_INFO, "%d, log info test", i);

}

closelog();

return 0;

}

2. alarm

[root@localhost ch08]# cat p8.5.alarm.c

#include <stdio.h>

#include <sys/types.h>

#include <sys/wait.h>

#include <unistd.h>

int main() {

int pid, wait_pid, status, i;

for(i=1;i<5;i++) {

pid=fork();

if(pid<0) {

perror("fork!");

return -1;

} else if(pid==0) {

printf("Child process(pid:%d), the process will be terminated in %d seconds./n", getpid(), i);

alarm(i);

pause();

}

}

while((wait_pid=wait(&status)) && wait_pid!=-1) {

if(WIFSIGNALED(status)) {

printf("process id: %d Received SIG : %d exit/n", pid, WTERMSIG(status));

}

if(WIFEXITED(status)) {

printf("process id: %d exit code : %d/n", pid, WEXITSTATUS(status));

}

}

return 0;

}

3. pipe

* 管道仅存在于父子或兄弟之间

* 命名管道可用于其它process之间

4. POSIX IPC

也就是System V IPC

包含：

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