我选择了 N 管道,我的问题: 捕获后,一个”
pipe
- 选择不起作用。可能我不会删除i
描述符。这是我的问题:vector
这样的动态数组并插入和删除i
我的代码:
while(1)
{
sel = select(val+1,&set,NULL,NULL,&timeout);
if(sel < 0)
perror("Blad funkcji select");
else if(sel == 0)
printf("Brak komunikatow \n");
else{
for(i = 0; i < val; i++)
{
if(FD_ISSET(fd[i][0],&set))
{
while(read(fd[i][0],&buf,rozmiar) > 0)
write(1,&buf,rozmiar);
} // check if exist and write to stdout
} // end SELECT
for(i = 0, j =0; i< val; i++)
{
FD_SET(fd[i][0], &set);
}
timeout.tv_sec = 4;
timeout.tv_usec = 0;
}
返回值顶部
On success, select() and pselect() return the number of file descriptors contained in the three returned descriptor sets (that is, the total number of bits that are set in readfds, writefds, exceptfds) which may be zero if the timeout expires before anything interesting happens. On error, -1 is returned, and errno is set to indicate the error; the file descriptor sets are unmodified, and timeout becomes undefined.
if(sel ==-1)
perror("Blad funkcji select");