usr/sys/proc.h

/*
 * One structure allocated per active
 * process. It contains all data needed
 * about the process while the
 * process may be swapped out.
 * Other per process data (user.h)
 * is swapped with the process.
 */
struct  proc
{
        char    p_stat;
        char    p_flag;
        char    p_pri;          /* priority, negative is high */
        char    p_sig;          /* signal number sent to this process */
        char    p_uid;          /* user id, used to direct tty signals */
        char    p_time;         /* resident time for scheduling */
        char    p_cpu;          /* cpu usage for scheduling */
        char    p_nice;         /* nice for scheduling */
        int     p_ttyp;         /* controlling tty */
        int     p_pid;          /* unique process id */
        int     p_ppid;         /* process id of parent */
        int     p_addr;         /* address of swappable image */
        int     p_size;         /* size of swappable image (*64 bytes) */
        int     p_wchan;        /* event process is awaiting */
        int     *p_textp;       /* pointer to text structure */
} proc[NPROC];

/* stat codes */
#define SSLEEP  1               /* sleeping on high priority */
#define SWAIT   2               /* sleeping on low priority */
#define SRUN    3               /* running */
#define SIDL    4               /* intermediate state in process creation */
#define SZOMB   5               /* intermediate state in process termination */
#define SSTOP   6               /* process being traced */

/* flag codes */
#define SLOAD   01              /* in core */
#define SSYS    02              /* scheduling process */
#define SLOCK   04              /* process cannot be swapped */
#define SSWAP   010             /* process is being swapped out */
#define STRC    020             /* process is being traced */
#define SWTED   040             /* another tracing flag */