/* * 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 *qlink; /* link for queueing processes */ 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 cpu usage */ int p_pgrp; /* name of process group leader */ 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 */ int p_clktim; /* time to alarm clock signal */ /* next two entries support itime sys call (BBN:JFH 5/78) */ int *p_itima; /* user address for itime counter */ int p_itime[2]; /* for saving time when process is stopped */ } proc[NPROC]; /* structures for queueing them */ struct { char *qlink; }; struct procq { int sem_count; /* semaphore count for list access */ char *sem_q; /* queue of processes waiting for this list */ char *qhead; /* head for the list itself */ }; struct procq Free_proc; /* list of free process entries */ struct procq Run_proc; /* list of runable processes */ struct procq Swap_ready;/* queue of processes to be swapped in */ struct semaphore { int sem_count; /* number of people waiting if any */ char *sem_q; /* place to let people wait */ }; /* stat codes */ #define SSLEEP 1 /* awaiting an event */ #define SWAIT 2 /* (abandoned state) */ #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 */ #define SNOSIG 0100 /* rand:bobg--process isn't to get quit or interrupts from controlling tty */ struct proc *MAXPROC; /* addr of highest process used */