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#include
#include
#include
#include
void main(int argc, char ** argv)
{
time_t now;
int childpid, fd, fdtablesize;
int error, in, out;
/*ºöÂÔÖÕ¶Ë I/OÐźÅ,STOPÐźÅ*/
signal(SIGTTOU,SIG_IGN);
signal(SIGTTIN,SIG_IGN);
signal(SIGTSTP,SIG_IGN);
signal(SIGHUP,SIG_IGN);
/*¸¸½ø³ÌÍ˳ö£¬³ÌÐò½øÈëºǫ́ÔËÐÐ*/
if( fork()!=0 )
{
exit(1);
}
if( setsid()<0 )
{
exit(1); /*´´½¨Ò»¸öеĻáÒé×é*/
}
/*×Ó½ø³ÌÍ˳ö£¬Ëï½ø³Ìʧȥ¿ØÖÆÖÕ¶ËÁË*/
if( fork()!=0 )
{
exit(1);
}
if( chdir("/tmp")==-1 )
{
exit(1);
}
/*¹Ø±Õ´ò¿ªµÄÎļþÃèÊö·û£¬°üÀ¨±ê×¼ÊäÈë¡¢±ê×¼Êä³öºÍ±ê×¼´íÎóÊä³ö*/
fd=0;
for(fdtablesize=getdtablesize(); fd< fdtablesize;fd++)
{
close(fd);
}
umask(0);/*ÖØÉèÎļþ´´½¨ÑÚÂë*/
signal(SIGCHLD,SIG_IGN);/*ºöÂÔSIGCHLDÐźÅ*/
/*´Ë´¦£¬¿ÉÒÔ×ö×Ô¼ºÏë×öµÄ·þÎñÀý³Ì´úÂë¡£Ò»°ãÊÇÒ»¸öËÀÑ­»·£¬Èç¹ûÒª¿ÉÒÔ¿ØÖƵÄÍ˳öµÄ»°£¬¿ÉÒÔÉèÖûñÈ¡Ðźš£ÏÂÃæÊ¾ÀýÒ»ÏÂÒ»¸öдlogµÄÀý³Ì
*/
/*дlog£¬²âÊÔ½á¹û*/
syslog(LOG_USER|LOG_INFO,"ÊØ»¤½ø³Ì²âÊÔ£¡\n");
while(1)
{
time(&now);
syslog(LOG_USER|LOG_INFO,"µ±Ç°Ê±¼ä£º\t%s\t\t\n",ctime(&now));
sleep(6);
}
}
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5,fopen·µ»ØÖ¸Õë,open·µ»ØÎļþÃèÊö·û(ÕûÊý).
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