#include <sys/acct.h>

DESCRIPTION

     The kernel maintains the following acct information structure for all
     processes. If a process terminates, and accounting is enabled, the kernel
     calls the acct(2) function call to prepare and append the record to the
     accounting file.

     /*
      * Accounting structures; these use a comp_t type which is a 3 bits base 8
      * exponent, 13 bit fraction ``floating point'' number.  Units are 1/AHZ
      * seconds.
      */
     typedef u_short comp_t;

     struct acct {
             char    ac_comm[10];    /* name of command */
             comp_t  ac_utime;       /* user time */
             comp_t  ac_stime;       /* system time */
             comp_t  ac_etime;       /* elapsed time */
             time_t  ac_btime;       /* starting time */
             uid_t   ac_uid;         /* user id */
             gid_t   ac_gid;         /* group id */
             short   ac_mem;         /* memory usage average */
             comp_t  ac_io;          /* count of IO blocks */
             dev_t   ac_tty;         /* controlling tty */
     #define AFORK   0x01            /* forked but not execed */
     #define ASU     0x02            /* used super-user permissions */
     #define ACOMPAT 0x04            /* used compatibility mode */
     #define ACORE   0x08            /* dumped core */
     #define AXSIG   0x10            /* killed by a signal */
             char    ac_flag;        /* accounting flags */
     };

     /*
      * 1/AHZ is the granularity of the data encoded in the comp_t fields.
      * This is not necessarily equal to hz.
      */
     #define AHZ     64

     #ifdef KERNEL
     struct vnode    *acctp;
     #endif

     If a terminated process was created by an execve(2),  the name of the ex-
     ecuted file (at most ten characters of it) is saved in the field ac_comm
     and its status is saved by setting one of more of the following flags in
     ac_flag: AFORK, ASU, ACOMPAT, ACORE and ASIG.

SEE ALSO

     acct(2),  accton(8),  execve(2),  lastcomm(1),  sa(8)