Linux系统调用之sysinfo函数解析

【sysinfo系统调用】

功能描述：
获取系统总体统计信息。

用法：
#include <sys/sysinfo.h>int sysinfo（struct sysinfo *info）;

参数：
info：指向sysinfo结构的指针，原型如下，Linux版本必须>=2.3.23（i386），或者>=2.3.48（其它平台）。struct sysinfo {
    long uptime;             /* Seconds since boot */
    unsigned long loads[3]; /* 1, 5, and 15 minute load averages */
    unsigned long totalram; /* Total usable main memory size */
    unsigned long freeram;   /* Available memory size */
    unsigned long sharedram; /* Amount of shared memory */
    unsigned long bufferram; /* Memory used by buffers */
    unsigned long totalswap; /* Total swap space size */
    unsigned long freeswap; /* swap space still available */
    unsigned short procs;    /* Number of current processes */
    unsigned long totalhigh; /* Total high memory size */
    unsigned long freehigh; /* Available high memory size */
    unsigned int mem_unit;   /* Memory unit size in bytes */
    char _f[20-2*sizeof（long）-sizeof（int）]; /* Padding for libc5 */
};
返回说明：
成功执行时，返回0。失败返回-1，errno被设为EFAULT。