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Elixir Cross Referencer

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/*
 * Copyright (c) 1984 through 2008, William LeFebvre
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 * 
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 * 
 *     * Neither the name of William LeFebvre nor the names of other
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * top - a top users display for Unix
 *
 * SYNOPSIS:  any hp9000 running hpux version 9
 *
 * DESCRIPTION:
 * This is the machine-dependent module for HPUX 9.
 * This makes top work on (at least) the following systems:
 *	hp9000s800
 *	hp9000s700
 * This may make top work on the following, but we aren't sure:
 *	hp9000s300
 *
 * LIBS: 
 *
 * CFLAGS: -DHAVE_GETOPT
 *
 * AUTHOR: Kevin Schmidt <kevin@mcl.ucsb.edu> 
 *         adapted from Christos Zoulas <christos@ee.cornell.edu>
 */

#include "config.h"
#include <sys/types.h>
#include <sys/signal.h>
#include <sys/param.h>

#include <stdio.h>
#include <nlist.h>
#include <math.h>
#include <sys/dir.h>
#include <sys/user.h>
#include <sys/proc.h>
#include <sys/dk.h>
#include <sys/vm.h>
#include <sys/file.h>
#include <sys/time.h>
#ifndef hpux
# define P_RSSIZE(p) (p)->p_rssize
# define P_TSIZE(p) (p)->p_tsize
# define P_DSIZE(p) (p)->p_dsize
# define P_SSIZE(p) (p)->p_ssize
#else
# include <sys/pstat.h>
# define __PST2P(p, field) \
    ((p)->p_upreg ? ((struct pst_status *) (p)->p_upreg)->field : 0)
# define P_RSSIZE(p) __PST2P(p, pst_rssize)
# define P_TSIZE(p) __PST2P(p, pst_tsize)
# define P_DSIZE(p) __PST2P(p, pst_dsize)
# define P_SSIZE(p) __PST2P(p, pst_ssize)
# ifdef __hp9000s700
#  define p_percentcpu(p) ((p)->p_pctcpu)
#  define p_time_exact(p) ((p)->p_time)
# else
/* The following 4 #defines are per HPUX-9.0's <sys/proc.h> */
#  define PCT_NORM 9       /* log2(PCT_BASE) */
#  define PCT_BASE (1<<PCT_NORM)
#  define p_percentcpu(p) ((p)->p_fractioncpu/(float)(PCT_BASE*HZ))
#  define p_time_exact(p) (time.tv_sec-((p)->p_swaptime))
# endif /* __hp9000s700 */
#endif /* hpux */

#include "top.h"
#include "machine.h"
#include "utils.h"

#define VMUNIX	"/hp-ux"
#define KMEM	"/dev/kmem"
#define MEM	"/dev/mem"
#ifdef DOSWAP
#define SWAP	"/dev/dmem"
#endif

/* get_process_info passes back a handle.  This is what it looks like: */

struct handle
{
    struct proc **next_proc;	/* points to next valid proc pointer */
    int remaining;		/* number of pointers remaining */
};

/* declarations for load_avg */
#include "loadavg.h"

/* define what weighted cpu is.  */
#define weighted_cpu(pct, pp) ((p_time_exact(pp)) == 0 ? 0.0 : \
			 ((pct) / (1.0 - exp((p_time_exact(pp)) * logcpu))))

/* what we consider to be process size: */
#define PROCSIZE(pp) (P_TSIZE(pp) + P_DSIZE(pp) + P_SSIZE(pp))

/* definitions for indices in the nlist array */
#define X_AVENRUN	0
#define X_CCPU		1
#define X_NPROC		2
#define X_PROC		3
#define X_TOTAL		4
#define X_CP_TIME	5
#define X_MPID		6

/*
 * Steinar Haug from University of Trondheim, NORWAY pointed out that 
 * the HP 9000 system 800 doesn't have _hz defined in the kernel.  He
 * provided a patch to work around this.  We've improved on this patch
 * here and set the constant X_HZ only when _hz is available in the
 * kernel.  Code in this module that uses X_HZ is surrounded with
 * appropriate ifdefs.
 */

#ifndef hp9000s300
#define X_HZ		7
#endif


static struct nlist nlst[] = {
    { "_avenrun" },		/* 0 */
    { "_cexp" },		/* 1 */
    { "_nproc" },		/* 2 */
    { "_proc" },		/* 3 */
    { "_total" },		/* 4 */
    { "_cp_time" },		/* 5 */
    { "_mpid" },		/* 6 */
#ifdef X_HZ
    { "_hz" },			/* 7 */
#endif
    { 0 }
};

/*
 *  These definitions control the format of the per-process area
 */

static char header[] =
  "  PID X        PRI NICE  SIZE   RES STATE   TIME   WCPU    CPU COMMAND";
/* 0123456   -- field to fill in starts at header+6 */
#define UNAME_START 6

#define Proc_format \
	"%5d %-8.8s %3d %4d %5s %5s %-5s %6s %5.2f%% %5.2f%% %s"

/* process state names for the "STATE" column of the display */
/* the extra nulls in the string "run" are for adding a slash and
   the processor number when needed */

char *state_abbrev[] =
{
    "", "sleep", "WAIT", "run\0\0\0", "start", "zomb", "stop"
};


static int kmem;

/* values that we stash away in _init and use in later routines */

static double logcpu;

/* these are retrieved from the kernel in _init */

static unsigned long proc;
static          int  nproc;
static          long hz;
static load_avg  ccpu;
static          int  ncpu = 0;

/* these are offsets obtained via nlist and used in the get_ functions */
static unsigned long mpid_offset;
static unsigned long avenrun_offset;
static unsigned long total_offset;
static unsigned long cp_time_offset;

/* these are for calculating cpu state percentages */

static long cp_time[CPUSTATES];
static long cp_old[CPUSTATES];
static long cp_diff[CPUSTATES];

/* these are for detailing the process states */

int process_states[7];
char *procstatenames[] = {
    "", " sleeping, ", " ABANDONED, ", " running, ", " starting, ",
    " zombie, ", " stopped, ",
    NULL
};

/* these are for detailing the cpu states */

int cpu_states[9];
char *cpustatenames[] = {
    "usr", "nice", "sys", "idle", "", "", "", "intr", "ker",
    NULL
};

/* these are for detailing the memory statistics */

long memory_stats[8];
char *memorynames[] = {
    "Real: ", "K act, ", "K tot  ", "Virtual: ", "K act, ",
    "K tot, ", "K free", NULL
};

/* these are for keeping track of the proc array */

static int bytes;
static int pref_len;
static struct proc *pbase;
static struct proc **pref;
static struct pst_status *pst;

/* these are for getting the memory statistics */

static int pageshift;		/* log base 2 of the pagesize */

/* define pagetok in terms of pageshift */

#define pagetok(size) ((size) << pageshift)

/* useful externals */
extern int errno;
extern char *sys_errlist[];

long lseek();
long time();

machine_init(statics)

struct statics *statics;

{
    register int i = 0;
    register int pagesize;

    if ((kmem = open(KMEM, O_RDONLY)) == -1) {
	perror(KMEM);
	return(-1);
    }
#ifdef hp9000s800
    /* 800 names don't have leading underscores */
    for (i = 0; nlst[i].n_name; nlst[i++].n_name++)
	continue;
#endif

    /* get the list of symbols we want to access in the kernel */
    (void) nlist(VMUNIX, nlst);
    if (nlst[0].n_type == 0)
    {
	fprintf(stderr, "top: nlist failed\n");
	return(-1);
    }

    /* make sure they were all found */
    if (check_nlist(nlst) > 0)
    {
	return(-1);
    }

    /* get the symbol values out of kmem */
    (void) getkval(nlst[X_PROC].n_value,   (int *)(&proc),	sizeof(proc),
	    nlst[X_PROC].n_name);
    (void) getkval(nlst[X_NPROC].n_value,  &nproc,		sizeof(nproc),
	    nlst[X_NPROC].n_name);
    (void) getkval(nlst[X_CCPU].n_value,   (int *)(&ccpu),	sizeof(ccpu),
	    nlst[X_CCPU].n_name);
#ifdef X_HZ
    (void) getkval(nlst[X_HZ].n_value,     (int *)(&hz),	sizeof(hz),
	    nlst[X_HZ].n_name);
#else
    hz = HZ;
#endif

    /* stash away certain offsets for later use */
    mpid_offset = nlst[X_MPID].n_value;
    avenrun_offset = nlst[X_AVENRUN].n_value;
    total_offset = nlst[X_TOTAL].n_value;
    cp_time_offset = nlst[X_CP_TIME].n_value;

    /* this is used in calculating WCPU -- calculate it ahead of time */
    logcpu = log(loaddouble(ccpu));

    /* allocate space for proc structure array and array of pointers */
    bytes = nproc * sizeof(struct proc);
    pbase = (struct proc *)malloc(bytes);
    pref  = (struct proc **)malloc(nproc * sizeof(struct proc *));
    pst   = (struct pst_status *)malloc(nproc * sizeof(struct pst_status));

    /* Just in case ... */
    if (pbase == (struct proc *)NULL || pref == (struct proc **)NULL)
    {
	fprintf(stderr, "top: can't allocate sufficient memory\n");
	return(-1);
    }

    /* get the page size with "getpagesize" and calculate pageshift from it */
    pagesize = getpagesize();
    pageshift = 0;
    while (pagesize > 1)
    {
	pageshift++;
	pagesize >>= 1;
    }

    /* we only need the amount of log(2)1024 for our conversion */
    pageshift -= LOG1024;

    /* fill in the statics information */
    statics->procstate_names = procstatenames;
    statics->cpustate_names = cpustatenames;
    statics->memory_names = memorynames;

    /* all done! */
    return(0);
}

char *format_header(uname_field)

register char *uname_field;

{
    register char *ptr;

    ptr = header + UNAME_START;
    while (*uname_field != '\0')
    {
	*ptr++ = *uname_field++;
    }

    return(header);
}

void
get_system_info(si)

struct system_info *si;

{
    load_avg avenrun[3];
    long total;

    /* get the cp_time array */
    (void) getkval(cp_time_offset, (int *)cp_time, sizeof(cp_time),
		   "_cp_time");

    /* get load average array */
    (void) getkval(avenrun_offset, (int *)avenrun, sizeof(avenrun),
		   "_avenrun");

    /* get mpid -- process id of last process */
    (void) getkval(mpid_offset, &(si->last_pid), sizeof(si->last_pid),
		   "_mpid");

    /* convert load averages to doubles */
    {
	register int i;
	register double *infoloadp;
	register load_avg *sysloadp;

	infoloadp = si->load_avg;
	sysloadp = avenrun;
	for (i = 0; i < 3; i++)
	{
	    *infoloadp++ = loaddouble(*sysloadp++);
	}
    }

    /* convert cp_time counts to percentages */
    total = percentages(CPUSTATES, cpu_states, cp_time, cp_old, cp_diff);

    /* sum memory statistics */
    {
	struct vmtotal total;

	/* get total -- systemwide main memory usage structure */
	(void) getkval(total_offset, (int *)(&total), sizeof(total),
		       "_total");
	/* convert memory stats to Kbytes */
	memory_stats[0] = -1;
	memory_stats[1] = pagetok(total.t_arm);
	memory_stats[2] = pagetok(total.t_rm);
	memory_stats[3] = -1;
	memory_stats[4] = pagetok(total.t_avm);
	memory_stats[5] = pagetok(total.t_vm);
	memory_stats[6] = pagetok(total.t_free);
    }

    /* set arrays and strings */
    si->cpustates = cpu_states;
    si->memory = memory_stats;
}

static struct handle handle;

caddr_t get_process_info(si, sel, i)

struct system_info *si;
struct process_select *sel;
int i;

{
    register int i;
    register int total_procs;
    register int active_procs;
    register struct proc **prefp;
    register struct proc *pp;

    /* these are copied out of sel for speed */
    int show_idle;
    int show_system;
    int show_uid;
    int show_command;

    /* read all the proc structures in one fell swoop */
    (void) getkval(proc, (int *)pbase, bytes, "proc array");
    for (i = 0; i < nproc; ++i) {
	if (pstat(PSTAT_PROC, &pst[i], sizeof(pst[i]), 0, pbase[i].p_pid) != 1)
	    pbase[i].p_upreg = (preg_t *) 0;
	else
	    pbase[i].p_upreg = (preg_t *) &pst[i];
	pbase[i].p_nice = pst[i].pst_nice;
	pbase[i].p_cpticks = pst[i].pst_cpticks;
    }


    /* get a pointer to the states summary array */
    si->procstates = process_states;

    /* set up flags which define what we are going to select */
    show_idle = sel->idle;
    show_system = sel->system;
    show_uid = sel->uid != -1;
    show_command = sel->command != NULL;

    /* count up process states and get pointers to interesting procs */
    total_procs = 0;
    active_procs = 0;
    memset((char *)process_states, 0, sizeof(process_states));
    prefp = pref;
    for (pp = pbase, i = 0; i < nproc; pp++, i++)
    {
	/*
	 *  Place pointers to each valid proc structure in pref[].
	 *  Process slots that are actually in use have a non-zero
	 *  status field.  Processes with SSYS set are system
	 *  processes---these get ignored unless show_sysprocs is set.
	 */
	if (pp->p_stat != 0 &&
	    (show_system || ((pp->p_flag & SSYS) == 0)))
	{
	    total_procs++;
	    process_states[pp->p_stat]++;
	    /*
	     * idle processes can be selectively ignored:  a process is
	     * considered idle when cpticks is zero AND it is not in the run
	     * state.  Zombies are always ignored.  We also skip over 
	     * processes that have been excluded via a uid selection
	     */
	    if ((pp->p_stat != SZOMB) &&
		(show_idle || (pp->p_cpticks != 0) || (pp->p_stat == SRUN)) &&
		(!show_uid || pp->p_uid == (uid_t)sel->uid))
	    {
		*prefp++ = pp;
		active_procs++;
	    }
	}
    }

    /* if requested, sort the "interesting" processes */
    if (compare != NULL)
    {
	qsort((char *)pref, active_procs, sizeof(struct proc *), proc_compare);
    }

    /* remember active and total counts */
    si->p_total = total_procs;
    si->p_active = pref_len = active_procs;

    /* pass back a handle */
    handle.next_proc = pref;
    handle.remaining = active_procs;
    return((caddr_t)&handle);
}

char fmt[MAX_COLS];		/* static area where result is built */

char *format_next_process(handle, get_userid)

caddr_t handle;
char *(*get_userid)();

{
    register struct proc *pp;
    register long cputime;
    register double pct;
    int where;
    struct user u;
    struct handle *hp;
    struct timeval time;
    struct timezone timezone;

    /* find and remember the next proc structure */
    hp = (struct handle *)handle;
    pp = *(hp->next_proc++);
    hp->remaining--;
    

    /* get the process's user struct and set cputime */
    where = getu(pp, &u);
    if (where == -1)
    {
	(void) strcpy(u.u_comm, "<swapped>");
	cputime = 0;
    }
    else
    {

	  
	/* set u_comm for system processes */
	if (u.u_comm[0] == '\0')
	{
	    if (pp->p_pid == 0)
	    {
		(void) strcpy(u.u_comm, "Swapper");
	    }
	    else if (pp->p_pid == 2)
	    {
		(void) strcpy(u.u_comm, "Pager");
	    }
	}
	if (where == 1) {
	    /*
	     * Print swapped processes as <pname>
	     */
	    char buf[sizeof(u.u_comm)];
	    (void) strncpy(buf, u.u_comm, sizeof(u.u_comm));
	    u.u_comm[0] = '<';
	    (void) strncpy(&u.u_comm[1], buf, sizeof(u.u_comm) - 2);
	    u.u_comm[sizeof(u.u_comm) - 2] = '\0';
	    (void) strncat(u.u_comm, ">", sizeof(u.u_comm) - 1);
	    u.u_comm[sizeof(u.u_comm) - 1] = '\0';
	}

	cputime = __PST2P(pp, pst_cptickstotal) / hz;
    }

    /* calculate the base for cpu percentages */
    pct = pctdouble(p_percentcpu(pp));

    /* get time used for calculation in weighted_cpu */
    gettimeofday(&time, &timezone);

    /* format this entry */
    sprintf(fmt,
	    Proc_format,
	    pp->p_pid,
	    (*get_userid)(pp->p_uid),
	    pp->p_pri - PZERO,
	    pp->p_nice - NZERO,
	    format_k(pagetok(PROCSIZE(pp))),
	    format_k(pagetok(P_RSSIZE(pp))),
	    state_abbrev[pp->p_stat],
	    format_time(cputime),
	    100.0 * weighted_cpu(pct, pp),
	    100.0 * pct,
	    printable(u.u_comm));

    /* return the result */
    return(fmt);
}

/*
 *  getu(p, u) - get the user structure for the process whose proc structure
 *	is pointed to by p.  The user structure is put in the buffer pointed
 *	to by u.  Return 0 if successful, -1 on failure (such as the process
 *	being swapped out).
 */


getu(p, u)

register struct proc *p;
struct user *u;

{
    struct pst_status *ps;
    char *s, *c;
    int i;

    if ((ps = (struct pst_status *) p->p_upreg) == NULL)
	return -1;

    memset(u, 0, sizeof(struct user));
    c = ps->pst_cmd;
    ps->pst_cmd[PST_CLEN - 1] = '\0';        /* paranoia */
    s = strtok(ps->pst_cmd, "\t \n");

    if (c = strrchr(s, '/'))
	c++;
    else
	c = s;
    if (*c == '-')
	c++;
    i = 0;
    for (; i < MAXCOMLEN; i++) {
	if (*c == '\0' || *c == ' ' || *c == '/')
	    break;
	u->u_comm[i] = *c++;
    }
#ifndef DOSWAP
    return ((p->p_flag & SLOAD) == 0 ? 1 : 0);
#endif
    return(0);
}

/*
 * check_nlist(nlst) - checks the nlist to see if any symbols were not
 *		found.  For every symbol that was not found, a one-line
 *		message is printed to stderr.  The routine returns the
 *		number of symbols NOT found.
 */

int check_nlist(nlst)

register struct nlist *nlst;

{
    register int i;

    /* check to see if we got ALL the symbols we requested */
    /* this will write one line to stderr for every symbol not found */

    i = 0;
    while (nlst->n_name != NULL)
    {
	if (nlst->n_type == 0)
	{
	    /* this one wasn't found */
	    fprintf(stderr, "kernel: no symbol named `%s'\n", nlst->n_name);
	    i = 1;
	}
	nlst++;
    }

    return(i);
}


/*
 *  getkval(offset, ptr, size, refstr) - get a value out of the kernel.
 *	"offset" is the byte offset into the kernel for the desired value,
 *  	"ptr" points to a buffer into which the value is retrieved,
 *  	"size" is the size of the buffer (and the object to retrieve),
 *  	"refstr" is a reference string used when printing error meessages,
 *	    if "refstr" starts with a '!', then a failure on read will not
 *  	    be fatal (this may seem like a silly way to do things, but I
 *  	    really didn't want the overhead of another argument).
 *  	
 */

getkval(offset, ptr, size, refstr)

unsigned long offset;
int *ptr;
int size;
char *refstr;

{
    if (lseek(kmem, (long)offset, L_SET) == -1) {
        if (*refstr == '!')
            refstr++;
        (void) fprintf(stderr, "%s: lseek to %s: %s\n", KMEM, 
		       refstr, strerror(errno));
        quit(23);
    }
    if (read(kmem, (char *) ptr, size) == -1) {
        if (*refstr == '!') 
            return(0);
        else {
            (void) fprintf(stderr, "%s: reading %s: %s\n", KMEM, 
			   refstr, strerror(errno));
            quit(23);
        }
    }
    return(1);
}
    
/* comparison routine for qsort */

/*
 *  proc_compare - comparison function for "qsort"
 *	Compares the resource consumption of two processes using five
 *  	distinct keys.  The keys (in descending order of importance) are:
 *  	percent cpu, cpu ticks, state, resident set size, total virtual
 *  	memory usage.  The process states are ordered as follows (from least
 *  	to most important):  WAIT, zombie, sleep, stop, start, run.  The
 *  	array declaration below maps a process state index into a number
 *  	that reflects this ordering.
 */

static unsigned char sorted_state[] =
{
    0,	/* not used		*/
    3,	/* sleep		*/
    1,	/* ABANDONED (WAIT)	*/
    6,	/* run			*/
    5,	/* start		*/
    2,	/* zombie		*/
    4	/* stop			*/
};
 
proc_compare(pp1, pp2)

struct proc **pp1;
struct proc **pp2;

{
    register struct proc *p1;
    register struct proc *p2;
    register int result;
    register pctcpu lresult;

    /* remove one level of indirection */
    p1 = *pp1;
    p2 = *pp2;

    /* compare percent cpu (pctcpu) */
    if ((lresult = p_percentcpu(p2) - p_percentcpu(p1)) == 0)
    {
	/* use cpticks to break the tie */
	if ((result = p2->p_cpticks - p1->p_cpticks) == 0)
	{
	    /* use process state to break the tie */
	    if ((result = sorted_state[p2->p_stat] -
			  sorted_state[p1->p_stat])  == 0)
	    {
		/* use priority to break the tie */
		if ((result = p2->p_pri - p1->p_pri) == 0)
		{
		    /* use resident set size (rssize) to break the tie */
		    if ((result = P_RSSIZE(p2) - P_RSSIZE(p1)) == 0)
		    {
			/* use total memory to break the tie */
			result = PROCSIZE(p2) - PROCSIZE(p1);
		    }
		}
	    }
	}
    }
    else
    {
	result = lresult < 0 ? -1 : 1;
    }

    return(result);
}


void (*signal(sig, func))()
    int sig;
    void (*func)();
{
    struct sigvec osv, sv;

    /*
     * XXX: we should block the signal we are playing with,
     *	    in case we get interrupted in here.
     */
    if (sigvector(sig, NULL, &osv) == -1)
	return BADSIG;
    sv = osv;
    sv.sv_handler = func;
#ifdef SV_BSDSIG
    sv.sv_flags |= SV_BSDSIG;
#endif
    if (sigvector(sig, &sv, NULL) == -1)
	return BADSIG;
    return osv.sv_handler;
}

int getpagesize() { return 1 << PGSHIFT; }

int setpriority(a, b, c) { errno = ENOSYS; return -1; }

/*
 * proc_owner(pid) - returns the uid that owns process "pid", or -1 if
 *		the process does not exist.
 *		It is EXTREMLY IMPORTANT that this function work correctly.
 *		If top runs setuid root (as in SVR4), then this function
 *		is the only thing that stands in the way of a serious
 *		security problem.  It validates requests for the "kill"
 *		and "renice" commands.
 */

int proc_owner(pid)

int pid;

{
    register int cnt;
    register struct proc **prefp;
    register struct proc *pp;

    prefp = pref;
    cnt = pref_len;
    while (--cnt >= 0)
    {
	if ((pp = *prefp++)->p_pid == (pid_t)pid)
	{
	    return((int)pp->p_uid);
	}
    }
    return(-1);
}