#include <iostream>
#include <unistd.h>
//#include
"curl/curl.h"
#include "app_curl.h"
#include
"youtube_package.h"
#include "CAutoMail.h"
#include
<fcntl.h>
#include <signal.h>
#include
<unistd.h>
#include <sys/types.h>
#include
<sys/stat.h>
#include <sys/resource.h>
#define
LOCKFILE "./daemon.pid"
#define LOCKMODE
(S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH)
int lockfile(int fd);
int
lockfile(int fd)
{
struct flock
fl;
fl.l_len=0;
fl.l_type=F_WRLCK;
fl.l_whence=SEEK_SET;
fl.l_start=0;
return
(fcntl(fd,F_SETLK,&fl));
}
int
already_running(void)
{
int fd;
char buf[16]={0};
int nResult=0;
if(0>(fd=open(LOCKFILE,O_RDWR|O_CREAT,LOCKMODE)))
{
COMM_LOG("youtube",LOG_ERROR,"can‘t open
%s:%s",LOCKFILE,strerror(errno));
exit(1);
}
if(lockfile(fd)<0)
{
if(errno==EACCES ||
errno==EAGAIN)
{
close(fd);
return 1;
}
COMM_LOG("youtube",LOG_ERROR,"can‘t lock
%s:%s",LOCKFILE,strerror(errno));
exit(1);
}
nResult=ftruncate(fd,0);
snprintf(buf,sizeof(buf),"%ld",(long)getpid());
nResult=write(fd,buf,strlen(buf)+1);
return 0;
}
void daemonize(const char
*cmd)
{
int i,fd0,fd1,fd2;
pid_t
pid;
struct rlimit rl;
struct
sigaction sa;
//umask(0);
if((pid=fork())<0)
{
COMM_LOG("youtube",LOG_ERROR,"%s","pid can‘t
fork");
exit(0);
}else if(pid!=0)
{
exit(0);
}
setsid();
sa.sa_handler=SIG_IGN;
sigemptyset(&sa.sa_mask);
sa.sa_flags=0;
if(sigaction(SIGHUP,&sa,NULL)<0)
{
COMM_LOG("youtube",LOG_ERROR,"%s","can‘t ignore SIGHUP");
exit(0);
}
if((pid=fork())<0)
{
COMM_LOG("youtube",LOG_ERROR,"%s","pid can‘t
fork");
exit(0);
}else if(pid!=0)
{
exit(0);
}
//if(chdir("/")<0)
//{
// COMM_LOG("youtube",LOG_ERROR,"%s","can‘t change
directory to /");
//
exit(0);
//}
if(rl.rlim_max==RLIM_INFINITY)
rl.rlim_max=1024;
for(i=0;i<rl.rlim_max;i++)
close(i);
fd0=open("/dev/null",O_RDWR);
fd1=dup(0);
fd2=dup(0);
if(fd0!=0 || fd1!=1 || fd2!=2)
{
COMM_LOG("youtube",LOG_ERROR,"%s,%d,%d,%d","unexpected
file descriprors",fd0,fd1,fd2);
exit(1);
}
}
int
main()
{
int ret=0;
#if 0
daemonize(NULL);
if(already_running())
{
COMM_LOG("youtube",LOG_ERROR,"%s","daemon already
running");
exit(1);
}
#endif
//CurlDownLoad("46.51.223.70/script/youtube_rev.ver","youtube_rev.ver",CurlWriteToFile);
// printf("hello world\n");
YtbDecrypt::GetInstance();//解密前置
//CAutoMail::GetInstance()->SendMail("test","this is a test
file!");
//CAutoMail::GetInstance()->SendMail("test","你好啊，中文测试！");
//printf("jiexi0--\n");
while(1)
{
sleep(10);
}
return
ret;
}
关系所有的文件描述符：
for(i=getdtablesize()-1;i>=0;--i)
close(i);
NAME
getdtablesize - get descriptor
table size
SYNOPSIS
#include
<unistd.h>
int
getdtablesize(void);
Feature Test Macro Requirements for
glibc (see feature_test_macros(7)):
getdtablesize():
Since glibc
2.12:
_BSD_SOURCE
||
!(_POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE >=
600)
Before
glibc
2.12:
_BSD_SOURCE || _XOPEN_SOURCE >= 500 || _XOPEN_SOURCE &&
_XOPEN_SOURCE_EXTENDED
DESCRIPTION
getdtablesize() returns the maximum number of files a
process can have open, one more than the largest possible value for a
file
descriptor.
RETURN VALUE
The current limit on the number of open files per
process.
ERRORS
On Linux,
getdtablesize() can return any of the errors described for getrlimit(2); see
NOTES below.
对服务器编程以改变它的控制TTY：
使进程与其控制终端分开：
fd=open("/dev/tty",0_RDWR);
(void)ioctl(fd,TIOCNOTTY,0);
(void)close(fd);
每个进程继承了一个进程组的成员关系，为避免接收其父进程有意义的下信号，服务器必须离开其父进程的进程组。
对服务器编程以设置其进程组：
(void)setpgrp(0,getpid());
原文地址：http://www.cnblogs.com/jingzhishen/p/3767687.html
