在linux下如何通过编程获得网络流量或cpu占用率？

[yflu]

3x

[axlw]

netstat
top

[yuanlei1978113]

一般这些信息都在/proc/这个目录下保存着：
网络信息：/proc/net/netstat
cpu信息：/proc/cpuinfo AND /proc/stat
你要获得这些信息时就读取这些文件即可。

[blh]

cpu占用率
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>

struct cpu_usage
{
unsigned long user;
unsigned long sys;
unsigned long nice;
unsigned long idle;

};

static struct cpu_usage old_cd, new_cd;
static tmp[64];
void get_cpu_data(struct cpu_usage *pcd)
{
FILE *file = NULL;
file = fopen("/proc/stat", "r");
if (file == NULL)
{
perror("fopen");
exit(-1);
}
memset(pcd, 0, sizeof(struct cpu_usage));
fscanf(file, "%s %lu %lu %lu %lu", tmp, &(pcd->user), &(pcd->sys), &(pcd->nice), &(pcd->idle
));
fclose(file);
}

void cpu_usage()
{
double user, sys, nice, idle, total;

get_cpu_data(&new_cd);
user = (double)(new_cd.user - old_cd.user);
sys = (double)(new_cd.sys - old_cd.sys);
nice = (double)(new_cd.nice - old_cd.nice);
idle = (double)(new_cd.idle - old_cd.idle);
total = user + sys + nice + idle;
memcpy(&old_cd, &new_cd, sizeof(struct cpu_usage));
fprintf(stdout, "CPU usage: %2.1f\%\n", (idle / total) * 100);
}


int main()
{
get_cpu_data(&old_cd);
while(1)
{
sleep(1);
cpu_usage();
}
return 0;
}

其实可以使用glibtop库实现
头文件在/usr/include/glibtop.h

[yflu]

uop什么意思？

[XSY_VC]

发

[liuty2006]

uop

[liuty2006]

up

[liuty2006]

run result as follow:
CPU usage: 97.0%
CPU usage: 97.0%
CPU usage: 99.0%
CPU usage: 97.0%
CPU usage: 95.0%
CPU usage: 81.2%
CPU usage: 94.1%
CPU usage: 92.1%

question:
should the "idle" be include in?