您需要从中解析出数据/proc/<PID>/stat。这些是前几个字段（来自Documentation/filesystems/proc.txt内核源代码）：

Table 1-3: Contents of the stat files (as of 2.6.22-rc3)
..............................................................................
 Field          Content
  pid           process id
  tcomm         filename of the executable
  state         state (R is running, S is sleeping, D is sleeping in an
                uninterruptible wait, Z is zombie, T is traced or stopped)
  ppid          process id of the parent process
  pgrp          pgrp of the process
  sid           session id
  tty_nr        tty the process uses
  tty_pgrp      pgrp of the tty
  flags         task flags
  min_flt       number of minor faults
  cmin_flt      number of minor faults with child's
  maj_flt       number of major faults
  cmaj_flt      number of major faults with child's
  utime         user mode jiffies
  stime         kernel mode jiffies
  cutime        user mode jiffies with child's
  cstime        kernel mode jiffies with child's

您可能在utime和/或之后stime。您还需要从中读取cpu行/proc/stat，如下所示：

cpu  192369 7119 480152 122044337 14142 9937 26747 0 0

这将告诉您已在各种类别中以累计量为单位使用的累计CPU时间。您需要对这条线上的值求和才能得到time_total度量。

同时读取utime并stime进行过程中，你有兴趣，并阅读time_total来自/proc/stat。然后睡一秒钟左右，然后再次阅读它们。现在，您可以使用以下命令计算采样时间内该进程的CPU使用率：

user_util = 100 * (utime_after - utime_before) / (time_total_after - time_total_before);
sys_util = 100 * (stime_after - stime_before) / (time_total_after - time_total_before);

合理？