如何在c語言的linux中創建計時器？

Question

我需要一個定時器，所以你能告訴我如何製作一個定時器，它會在每一毫秒中斷我，然後我將有一個變量來計算毫秒數，然後每20毫秒我會調用主函數？

Answer 1

如果沒有別的事情可做，然後等待20毫秒，然後做一些事情，然後再等待，下面的方法會做：

#include <sys/time.h> 
#include <sys/types.h> 
#include <unistd.h> 

int main() 
{ 
    while (1) 
    { 
    struct timeval tv = {0, 20000}; /* 0 seconds, 20000 micro secs = 20 milli secs */ 

    if (-1 == select(0, NULL, NULL, NULL, &tv)) 
    { 
     if (EINTR == errno) 
     { 
     continue; /* this means the process received a signal during waiting, just start over waiting. However this could lead to wait cycles >20ms and <40ms. */ 
     } 

     perror("select()"); 
     exit(1); 
    } 

    /* do something every 20 ms */ 
    } 

    return 0; 
}