linux内核中得到内存的使用情况 si_meminfo

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 short pad; / explicit padding for m68k /
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[20-2sizeof(long)-sizeof(int)]; / Padding: libc5 uses this.. */
};

si_meminfo(struct sysinfo *val)