getrusage 函數簡介及使用

#include <sys/types.h>
w�o.a6/0T-r&Q0 #include <sys/time.h>
&[(F.i |!I[*w9?0 #include <sys/resource.h>我是網管部落格)~ID6U$V)_R1Tib2g
  
-@,eI5Rq9_s"H0 #define   RUSAGE_SELF     0
o/n.aws.Nn)g"^0X0 #define   RUSAGE_CHILDREN     -1我是網管部落格e~,q3g3X)xLKx
  
R+OzfX0 int   getrusage(int who, struct rusage *rusage);

getrusage函數有兩個參數。第一個參數可以設定為RUSAGE_SELF或者RUSAGE_CHILDREN。如果設定成 RUSAGE_SELF，那麼將會以當前進程的相關資訊來填充rusage(資料)結構。反之，如果設定成RUSAGE_CHILDREN，那麼 rusage結構中的資料都將是當前進程的子進程的資訊。

rusage(資料)結構定義在/usr/include/sys/resource.h中。它含有以下成員變數：

struct   rusage {我是網管部落格;L+VR9o ?2gF(gUR
      struct timeval ru_utime;   /* user time used */
pT~mI/v0P_0      struct timeval ru_stime;   /* system time used */我是網管部落格,Xa4f v9K
      long  ru_maxrss;           /* max resident set size */
9T1e'QV v(|0      long  ru_ixrss;            /* integral shared memory size */我是網管部落格+u Z;x;@(N@9Z
      long  ru_idrss;            /* integral unshared data */
6SS+}!CO1t0      long  ru_isrss;            /* integral unshared stack */我是網管部落格�w4aOh5hU
      long  ru_minflt;           /* page reclaims */
i3q&r$v)/gO0      long  ru_majflt;           /* page faults */
1m1/0G!a`$m0a0      long  ru_nswap;            /* swaps */
1`I5N a*H$t)q`V0}%a0      long  ru_inblock;          /* block input operations */我是網管部落格u7t/&y?(paX
      long  ru_oublock;          /* block output operations */我是網管部落格/PNU'F(Mrf'u'Z�rD
      long  ru_msgsnd;           /* messages sent */
Wk ^]d!gF0      long  ru_msgrcv;           /* messages received */我是網管部落格;m#_:m~}/Mv?
      long  ru_nsignals;         /* signals received */我是網管部落格?7g�T o{H
      long  ru_nvcsw;            /* voluntary context switches */
7{He8y5a-{#P_n0      long  ru_nivcsw;           /* involuntary " */
QJPCb0ep {0  };
樣本:
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/time.h>
#include <sys/resource.h>
int
main(int argc, char **argv)
{

    struct rusage buf;

   
    if(argc == 2) {
      system(argv[1]);
    }else {
      fprintf(stderr,"./getrusage  /"ls -l >/dev/null/"/n");
      exit(0);
    }
    int err = getrusage(RUSAGE_CHILDREN, &buf);
    //int err = getrusage(RUSAGE_SELF, &buf);
    printf("ERR=%d/n", err);
    printf("%20s:%ld/%ld/t%s/n", "ru_utime",
       buf.ru_utime.tv_sec, buf.ru_utime.tv_usec,
       "user time used (secs/usecs)");
    printf("%20s:%ld/%ld/t%s/n", "ru_stime",
       buf.ru_stime.tv_sec,
       buf.ru_stime.tv_usec,
       "system time used (secs/usecs)");
    printf("%20s:%-10ld/t%s/n",
       "ru_maxrss",
       buf.ru_maxrss,
       "maximum resident set size");
    printf("%20s:%-10ld/t%s/n",
       "ru_ixrss",
       buf.ru_ixrss,
       "integral shared memory size");
    printf("%20s:%-10ld/t%s/n",
       "ru_idrss",
       buf.ru_idrss,
       "integral unshared data size");
    printf("%20s:%-10ld/t%s/n",
       "ru_isrss",
       buf.ru_isrss,
       "integral unshared data stack size");
    printf("%20s:%-10ld/t%s/n",
       "ru_minflt",
       buf.ru_minflt,
       "page reclaims");
    printf("%20s:%-10ld/t%s/n",
       "ru_majflt",
       buf.ru_majflt,
       "page faults");
    printf("%20s:%-10ld/t%s/n",
       "ru_nswap",
       buf.ru_nswap,
       "swaps");
    printf("%20s:%-10ld/t%s/n",
       "ru_inblock",
       buf.ru_inblock,
       "block input operations");
    printf("%20s:%-10ld/t%s/n",
       "ru_oublock",
       buf.ru_oublock,
       "block output operations");
    printf("%20s:%-10ld/t%s/n",
       "ru_msgsnd",
       buf.ru_msgsnd,
       "messages sent");
    printf("%20s:%-10ld/t%s/n",
       "ru_msgrcv",
       buf.ru_msgrcv,
       "messages received");
    printf("%20s:%-10ld/t%s/n",
       "ru_nsignals",
       buf.ru_nsignals,
       "signals received");
    printf("%20s:%-10ld/t%s/n",
       "ru_nvcsw",
       buf.ru_nvcsw,
       "voluntary context switches");
    printf("%20s:%-10ld/t%s/n",
       "ru_nivcsw",
       buf.ru_nivcsw,
       "involuntary context switches");
  exit(0);
}