sigpending函数失效问题？
代码如下：
#include <stdio.h>
#include <signal.h>
#include <stdarg.h>
#include <time.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
void sighandler(int signum);
char buffer[200];
int main(void)
{
sigset_t blockset;
sigset_t pending;
int pendingcount;
strcpy(buffer, "None\n ");
printf( "thread id is %d.\n ",getpid());
if(signal(SIGINT,&sighandler)==SIG_ERR)
{
printf( "couldn 't register SIGINT\n ");
}
if(signal(SIGTERM,&sighandler)==SIG_ERR)
{
printf( "couldn 't register SIGTERM\n ");
}
if(signal(SIGCONT,&sighandler)==SIG_ERR)
{
printf( "couldn 't register SIGCONT\n ");
}

sigemptyset(&blockset);
sigemptyset(&pending);
// sigaddset(&blockset,SIGINT);
sigaddset(&blockset,SIGTERM);
for(;;)
{
sigprocmask(SIG_BLOCK,&blockset,NULL);
fgets(buffer,sizeof(buffer),stdin);
printf( "input %s\n ",buffer);
sigpending(&pending);
pendingcount=0;
if(sigismember(&pending,SIGINT))
{
pendingcount++;
printf( "SIGINT IS MEMBER ");
}

if(sigismember(&pending,SIGTERM))
{
pendingcount++;
printf( "SIGTERM IS MEMBER ");

}
if(pendingcount)
{
printf( "there are %d signals\n ",pendingcount);
}
sigprocmask(SIG_UNBLOCK,&blockset,NULL);
}
return 0;
}
void sighandler(int signumber)
{
printf( "caught sight %d.\n ",signumber);

}
照理上应该会输出： "SIGTERM IS MEMBER " 但实际运行并没有输出，这是为什么啊？

[解决办法]
在其他终端执行kill pid //pid为你的程序的进程号

在你执行程序的终端敲回车就出来了