NAME
acct —
execution accounting file
SYNOPSIS
#include
<sys/acct.h>
DESCRIPTION
The kernel maintains the following acct information structure for all processes. If a process terminates or misbehaves in specific ways, 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_int16_t comp_t;
struct acct {
char ac_comm[10]; /* command name */
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 */
u_int16_t ac_mem; /* average memory usage */
comp_t ac_io; /* count of IO blocks */
dev_t ac_tty; /* controlling tty */
#define AFORK 0x01 /* fork'd but not exec'd */
#define AMAP 0x04 /* system call or stack mapping violation */
#define ACORE 0x08 /* dumped core */
#define AXSIG 0x10 /* killed by a signal */
#define APLEDGE 0x20 /* killed due to pledge violation */
#define ATRAP 0x40 /* memory access violation */
#define AUNVEIL 0x80 /* unveil access violation */
u_int8_t 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
int acct_process(struct proc *p);
int acct_shutdown(void);
#endif
If a terminated or misbehaving process was created by an execve(2), the name of the executed file (at most ten characters of it) is saved in the field ac_comm and its status is saved by setting one or more of the following flags in ac_flag:
AFORK- A new process was created via fork(2) that was not followed by a call to execve(2).
AMAP- The process terminated abnormally due to a system call or stack mapping violation.
ACORE- The process terminated abnormally due to a signal and dumped core(5).
AXSIG- The process was killed by a signal(3).
APLEDGE- The process was killed due to a pledge(2) violation.
ATRAP- The process was killed due to a memory access violation detected by a processor trap.
AUNVEIL- The process attempted a file access that was prevented by unveil(2) restrictions. Note that this does not cause the process to terminate.
SEE ALSO
lastcomm(1), acct(2), execve(2), pledge(2), unveil(2), signal(3), core(5), accton(8), sa(8)
HISTORY
An acct file format first appeared in
Version 7 AT&T UNIX.