#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
#include <signal.h>
#include <unistd.h>
void my_handler ( timer_t timerid)
{
printf("\nHello World\n");
}
int main()
{
// declare some variables
timer_t timerid;
struct itimerspec itime;
struct sigevent sevp;
// initalize the sigevent variable
// the memset is necessary to avoid segmentation faults
memset (&sevp, 0, sizeof (struct sigevent));
sevp.sigev_notify=SIGEV_THREAD;
sevp.sigev_notify_function=(void *)my_handler;
timer_create (CLOCK_REALTIME, &sevp, &timerid);
// initialize the timer specification
// currently the offset and the period is 5 seconds // you have to adjust this to your actual needs
itime.it_value.tv_sec = 5;
itime.it_value.tv_nsec = 0;
itime.it_interval.tv_sec = 5;
itime.it_interval.tv_nsec = 0;
// create the timer
timer_settime (timerid, 0, &itime, NULL);
// this loop has to be adapted, so that the program ends after some time while(1){
// sleep(100);
}
错误:
Invoking: GCC C Compiler
gcc -O0 -g3 -Wall -c -fmessage-length=0 -MMD -MP -MF"src/new.d" -MT"src/new.d" -o "src/new.o" In 'CLOCK_REALTIME' undeclared (first use in this function)
Field 'tv_nsec' could not be resolved Semantic Error
Field 'tv_nsec' could not be resolved Semantic Error
Field 'tv_sec' could not be resolved Semantic Error
Field 'tv_sec' could not be resolved Semantic Error
storage size of 'itime' isn't known C/C++ Problem
我正在使用带有 Eclipse IDE 的 Linux 操作系统。
在开头添加
#include <time.h>
。
你需要两件小东西。
如上所述,
#include <time.h>
timer_create
需要一个feature_test_macro关于 (2),当您查看
time_create
的手册页时,在概要区域中,它会告诉您哪些函数需要特定的宏。
因此,快速解决方案是将以下 定义为上面代码中的第一行,然后在其后的某处添加
time.h
标头。
#define _POSIX_C_SOURCE 199309L
更长的解决方案是阅读
feature_test_macro
手册页,因为你会一直遇到这种事情。
顺便说一句,请确保再次链接
librt
,即-lrt