src/rt/persist.c

#ifndef lint
static const char       RCSid[] = "$Id: persist.c,v 2.44 2016/03/06 01:13:18 schorsch Exp $";
#endif
/*
 * Routines for persistent rtrace and rpict processes.
 *
 *  External symbols declared in ray.h
 */

#include "copyright.h"

#include <string.h>
#include <signal.h>
#include <sys/stat.h>
#include <sys/types.h>

#include "platform.h"
#ifndef NON_POSIX /* XXX need abstraction for process management */
 #include <sys/wait.h>
#endif

#include "rtprocess.h" /* getpid() */
#include "standard.h"
#include "random.h"
#include "ray.h"

#ifdef F_SETLKW
#include "selcall.h"

#ifndef TIMELIM
#define TIMELIM         (8*3600)        /* time limit for holding pattern */
#endif

extern int      headismine;     /* boolean true if header belongs to me */
extern char     *progname;      /* global program name */
extern char     *errfile;       /* global error file name */
static char     *persistfname = NULL;   /* persist file name */
static int      persistfd = -1;         /* persist file descriptor */
static char     inpname[TEMPLEN+1], outpname[TEMPLEN+1], errname[TEMPLEN+1];

typedef void (rsighandler_t)(int);
static rsighandler_t sig_io;
static rsighandler_t sig_alrm;


void
pfdetach(void)          /* release persist (and header) resources */
{
        if (persistfd >= 0)
                close(persistfd);
        persistfd = -1;
        persistfname = NULL;
        inpname[0] = '\0';
        outpname[0] = '\0';
        errname[0] = '\0';
        headismine = 0;
}


void
pfclean(void)           /* clean up persist files */
{
        if (persistfd >= 0)
                close(persistfd);
        if (persistfname != NULL)
                unlink(persistfname);
        if (inpname[0])
                unlink(inpname);
        if (outpname[0])
                unlink(outpname);
        if (errname[0])
                unlink(errname);
}


void
pflock(         /* place or release exclusive lock on file */
        int     lf
)
{
        struct flock    fls;

        fls.l_type = lf ? F_WRLCK : F_UNLCK;
        fls.l_whence = 0;
        fls.l_start = 0L;
        fls.l_len = 0L;
        if (fcntl(persistfd, F_SETLKW, &fls) < 0)
                error(SYSTEM, "cannot (un)lock persist file");
}


void
persistfile(    /* open persist file and lock it */
        char    *pfn
)
{
        persistfd = open(pfn, O_WRONLY|O_CREAT|O_EXCL, 0644);
        if (persistfd >= 0) {
                persistfname = pfn;
                pflock(1);
                return;
        }
                                /* file exists -- switch to i/o process */
        persistfd = open(pfn, O_RDWR);
        if (persistfd < 0) {
                sprintf(errmsg, "cannot open persist file \"%s\"", pfn);
                error(SYSTEM, errmsg);
        }
        pflock(1);
        io_process();   /* never returns */
}


static int      got_io;

static void sig_io(int i) { got_io++; }

static void sig_alrm(int i) { quit(0); }


void
pfhold(void)            /* holding pattern for idle rendering process */
{
        rsighandler_t   *oldalrm;
        char    buf[512];
        int     n;
                                /* close input and output descriptors */
        close(0);
        close(1);
        if (errfile == NULL)
                close(2);
                                /* create named pipes for input and output */
        if (mkfifo(mktemp(strcpy(inpname,TEMPLATE)), 0600) < 0)
                goto createrr;
        if (mkfifo(mktemp(strcpy(outpname,TEMPLATE)), 0600) < 0)
                goto createrr;
        if (errfile == NULL &&
                mkfifo(mktemp(strcpy(errname,TEMPLATE)), 0600) < 0)
                goto createrr;
        sprintf(buf, "%s %d\n%s\n%s\n%s\n", progname, getpid(),
                        inpname, outpname, errname);
        n = strlen(buf);
        if (write(persistfd, buf, n) < n)
                error(SYSTEM, "error writing persist file");
        lseek(persistfd, (off_t)0, SEEK_SET);
                                /* wait TIMELIM for someone to signal us */
        got_io = 0;
        signal(SIGIO, sig_io);
        oldalrm = signal(SIGALRM, sig_alrm);
        alarm(TIMELIM);
        pflock(0);                      /* unlock persist file for attach */
        while (!got_io)
                pause();                /* wait for attach */
        alarm(0);                       /* turn off alarm */
        signal(SIGALRM, oldalrm);
        signal(SIGIO, SIG_DFL);
        pflock(1);                      /* grab persist file back */
                                /* someone wants us; reopen stdin and stdout */
        close(0);
        if (open(inpname, O_RDONLY) != 0)
                error(INTERNAL, "unexpected stdin file number");
        clearerr(stdin);
        close(1);
        if (open(outpname, O_WRONLY) != 1)
                error(INTERNAL, "unexpected stdout file number");
        sleep(3);               /* give them a chance to open their pipes */
        if (errname[0]) {
                close(2);
                if (open(errname, O_WRONLY) != 2)
                        error(INTERNAL, "unexpected stderr file number");
                unlink(errname);
                errname[0] = '\0';
        }
        unlink(inpname);
        inpname[0] = '\0';
        unlink(outpname);
        outpname[0] = '\0';
        return;
createrr:
        error(SYSTEM, "cannot create named pipes in pfhold");
}


void
io_process(void)                /* just act as go-between for actual process */
{
        char    *cp;
        int     nr, n;
        char    buf[BUFSIZ], *pfin, *pfout, *pferr;
        int     pid, nfds;
        int     fdout, fderr = -1;
        int     status = 0;
        fd_set  readfds, excepfds;
                                        /* load persist file */
        n = 40;
        while ((nr = read(persistfd, buf, sizeof(buf)-1)) == 0) {
                if (!n--)
                        error(USER, "unattended persist file?");
                pflock(0);
                sleep(3+(3*getpid()+random())%13);      /* wait until ready */
                pflock(1);
        }
        if (nr < 0)
                error(SYSTEM, "error reading persist file");
        ftruncate(persistfd, (off_t)0L);        /* truncate persist file */
        pfdetach();                     /* close & release persist file */
        buf[nr] = '\0';                 /* parse what we got */
        if ((cp = strchr(buf, ' ')) == NULL)
                goto formerr;
        *cp++ = '\0';
        if ((pid = atoi(cp)) <= 0)
                goto formerr;
        if ((cp = strchr(cp, '\n')) == NULL)
                goto formerr;
        pfin = ++cp;
        if ((cp = strchr(cp, '\n')) == NULL)
                goto formerr;
        *cp++ = '\0';
        pfout = cp;
        if ((cp = strchr(cp, '\n')) == NULL)
                goto formerr;
        *cp++ = '\0';
        pferr = cp;
        if ((cp = strchr(cp, '\n')) == NULL)
                goto formerr;
        *cp++ = '\0';
        if (cp-buf != nr)
                goto formerr;
        if (strcmp(buf, progname)) {
                sprintf(errmsg, "persist file for %s, not %s", buf, progname);
                error(USER, errmsg);
        }
                                        /* wake up rendering process */
        if (kill(pid, SIGIO) < 0)
                error(SYSTEM, "cannot signal rendering process in io_process");
                                        /* fork child feeder process */
        pid = fork();
        if (pid < 0)
                error(SYSTEM, "fork failed in io_process");
        if (pid == 0) {                 /* feeder loop */
                int     fdin;
                close(1);               /* open input pipe */
                if ((fdin = open(pfin, O_WRONLY)) < 0)
                        error(SYSTEM, "cannot open feed pipe in io_process");
                                                /* renderer stdin */
                while ((nr = read(0, cp=buf, sizeof(buf))) > 0) {
                        do {
                                if ((n = write(fdin, cp, nr)) <= 0)
                                        goto writerr;
                                cp += n;
                        } while ((nr -= n) > 0);
                }
                if (nr < 0)
                        goto readerr;
                _exit(0);
        }
        close(0);
                                        /* open output pipes, in order */
        if ((fdout = open(pfout, O_RDONLY)) < 0)
                error(SYSTEM, "cannot open output pipe in io_process");
        if (pferr[0] && (fderr = open(pferr, O_RDONLY)) < 0)
                error(SYSTEM, "cannot open error pipe in io_process");
        for ( ; ; ) {                   /* eater loop */
                FD_ZERO(&readfds);
                FD_ZERO(&excepfds);
                nfds = 0;
                if (fdout >= 0) {
                        FD_SET(fdout, &readfds);
                        FD_SET(fdout, &excepfds);
                        nfds = fdout+1;
                }
                if (fderr >= 0) {
                        FD_SET(fderr, &readfds);
                        FD_SET(fderr, &excepfds);
                        nfds = fderr+1;
                }
                if (nfds == 0)
                        break;                  /* all done, exit */
                if (select(nfds, &readfds, NULL, &excepfds, NULL) < 0)
                        error(SYSTEM, "error in select call in io_process");
                                                /* renderer stderr */
                if (fderr >= 0 && (FD_ISSET(fderr, &readfds) ||
                                FD_ISSET(fderr, &excepfds))) {
                        nr = read(fderr, cp=buf, sizeof(buf));
                        if (nr < 0)
                                goto readerr;
                        if (nr == 0) {
                                close(fderr);
                                /* close(2);    don't close stderr! */
                                fderr = -1;
                        } else {
                                cp[nr] = '\0';  /* deduce status if we can */
                                n = strlen(progname);
                                if (!strncmp(cp, progname, n) &&
                                                cp[n++] == ':' &&
                                                cp[n++] == ' ') {
                                        struct erract   *ep;
                                        for (ep = erract; ep < erract+NERRS;
                                                        ep++)
                                                if (ep->pre[0] &&
                                                        !strncmp(cp+n, ep->pre,
                                                            strlen(ep->pre))) {
                                                        status = ep->ec;
                                                        break;
                                                }
                                }
                                do {            /* write message */
                                        if ((n = write(2, cp, nr)) <= 0)
                                                goto writerr;
                                        cp += n;
                                } while ((nr -= n) > 0);
                        }
                }
                                                /* renderer stdout */
                if (fdout >= 0 && (FD_ISSET(fdout, &readfds) ||
                                FD_ISSET(fdout, &excepfds))) {
                        nr = read(fdout, cp=buf, sizeof(buf));
                        if (nr < 0)
                                goto readerr;
                        if (nr == 0) {          /* EOF */
                                close(fdout);
                                close(1);
                                fdout = -1;
                        } else
                                do {            /* write it all */
                                        if ((n = write(1, cp, nr)) <= 0)
                                                goto writerr;
                                        cp += n;
                                } while ((nr -= n) > 0);
                }
        }
        kill(pid, SIGTERM);     /* no more process to feed, so... */
        waitpid(pid, 0, 0);     /* wait for feeder process */
        _exit(status);
formerr:
        error(USER, "format error in persist file");
readerr:
        error(SYSTEM, "read error in io_process");
writerr:
        error(SYSTEM, "write error in io_process");
}

#else

void pfclean(void) {}

#endif
Revision:	2.45
Committed:	Sat Jun 7 05:09:46 2025 UTC (19 hours, 34 minutes ago) by greg
Content type:	text/plain
Branch:	MAIN
CVS Tags:	HEAD
Changes since 2.44:	+1 -2 lines
Log Message:	refactor: Put some declarations into "paths.h" and included in "platform.h"
#	User	Rev	Content
1	greg	2.1	#ifndef lint
2	greg	2.45	static const char RCSid[] = "$Id: persist.c,v 2.44 2016/03/06 01:13:18 schorsch Exp $";
3	greg	2.1	#endif
4			/*
5			* Routines for persistent rtrace and rpict processes.
6	greg	2.26	*
7			* External symbols declared in ray.h
8			*/
9
10	greg	2.27	#include "copyright.h"
11	greg	2.1
12	schorsch	2.29	#include <string.h>
13			#include <signal.h>
14			#include <sys/stat.h>
15	schorsch	2.38	#include <sys/types.h>
16	schorsch	2.40
17			#include "platform.h"
18	schorsch	2.39	#ifndef NON_POSIX /* XXX need abstraction for process management */
19			#include <sys/wait.h>
20			#endif
21	schorsch	2.29
22	schorsch	2.30	#include "rtprocess.h" /* getpid() */
23	greg	2.1	#include "standard.h"
24	gregl	2.25	#include "random.h"
25	schorsch	2.34	#include "ray.h"
26	greg	2.6
27			#ifdef F_SETLKW
28	gregl	2.21	#include "selcall.h"
29	greg	2.1
30	greg	2.2	#ifndef TIMELIM
31			#define TIMELIM (83600) / time limit for holding pattern */
32	greg	2.26	#endif
33
34	greg	2.1	extern int headismine; /* boolean true if header belongs to me */
35	greg	2.12	extern char progname; / global program name */
36	greg	2.14	extern char errfile; / global error file name */
37	greg	2.1	static char persistfname = NULL; / persist file name */
38			static int persistfd = -1; /* persist file descriptor */
39	schorsch	2.34	static char inpname[TEMPLEN+1], outpname[TEMPLEN+1], errname[TEMPLEN+1];
40	greg	2.1
41	greg	2.42	typedef void (rsighandler_t)(int);
42			static rsighandler_t sig_io;
43			static rsighandler_t sig_alrm;
44	greg	2.1
45
46	greg	2.43	void
47	schorsch	2.34	pfdetach(void) /* release persist (and header) resources */
48	greg	2.1	{
49			if (persistfd >= 0)
50			close(persistfd);
51			persistfd = -1;
52			persistfname = NULL;
53			inpname[0] = '\0';
54			outpname[0] = '\0';
55	greg	2.14	errname[0] = '\0';
56	greg	2.1	headismine = 0;
57			}
58
59
60	greg	2.43	void
61	schorsch	2.34	pfclean(void) /* clean up persist files */
62	greg	2.1	{
63			if (persistfd >= 0)
64			close(persistfd);
65			if (persistfname != NULL)
66			unlink(persistfname);
67			if (inpname[0])
68			unlink(inpname);
69			if (outpname[0])
70			unlink(outpname);
71	greg	2.14	if (errname[0])
72			unlink(errname);
73	greg	2.1	}
74
75
76	greg	2.43	void
77	schorsch	2.34	pflock( /* place or release exclusive lock on file */
78			int lf
79			)
80	greg	2.1	{
81			struct flock fls;
82
83			fls.l_type = lf ? F_WRLCK : F_UNLCK;
84			fls.l_whence = 0;
85			fls.l_start = 0L;
86			fls.l_len = 0L;
87			if (fcntl(persistfd, F_SETLKW, &fls) < 0)
88			error(SYSTEM, "cannot (un)lock persist file");
89			}
90
91
92	greg	2.43	void
93	schorsch	2.34	persistfile( /* open persist file and lock it */
94			char *pfn
95			)
96	greg	2.1	{
97	greg	2.13	persistfd = open(pfn, O_WRONLY\|O_CREAT\|O_EXCL, 0644);
98	greg	2.1	if (persistfd >= 0) {
99			persistfname = pfn;
100			pflock(1);
101			return;
102			}
103			/* file exists -- switch to i/o process */
104			persistfd = open(pfn, O_RDWR);
105			if (persistfd < 0) {
106			sprintf(errmsg, "cannot open persist file \"%s\"", pfn);
107			error(SYSTEM, errmsg);
108			}
109			pflock(1);
110			io_process(); /* never returns */
111			}
112
113
114	greg	2.13	static int got_io;
115	greg	2.1
116	schorsch	2.34	static void sig_io(int i) { got_io++; }
117	greg	2.1
118	schorsch	2.34	static void sig_alrm(int i) { quit(0); }
119	greg	2.13
120
121	greg	2.43	void
122	schorsch	2.34	pfhold(void) /* holding pattern for idle rendering process */
123	greg	2.1	{
124	greg	2.42	rsighandler_t *oldalrm;
125	greg	2.12	char buf[512];
126	greg	2.43	int n;
127	greg	2.1	/* close input and output descriptors */
128	greg	2.37	close(0);
129			close(1);
130	greg	2.16	if (errfile == NULL)
131	greg	2.37	close(2);
132	greg	2.1	/* create named pipes for input and output */
133	greg	2.26	if (mkfifo(mktemp(strcpy(inpname,TEMPLATE)), 0600) < 0)
134	greg	2.1	goto createrr;
135	greg	2.26	if (mkfifo(mktemp(strcpy(outpname,TEMPLATE)), 0600) < 0)
136	greg	2.1	goto createrr;
137	greg	2.14	if (errfile == NULL &&
138	greg	2.26	mkfifo(mktemp(strcpy(errname,TEMPLATE)), 0600) < 0)
139	greg	2.14	goto createrr;
140			sprintf(buf, "%s %d\n%s\n%s\n%s\n", progname, getpid(),
141			inpname, outpname, errname);
142	greg	2.1	n = strlen(buf);
143			if (write(persistfd, buf, n) < n)
144	greg	2.10	error(SYSTEM, "error writing persist file");
145	greg	2.32	lseek(persistfd, (off_t)0, SEEK_SET);
146	greg	2.2	/* wait TIMELIM for someone to signal us */
147	greg	2.13	got_io = 0;
148			signal(SIGIO, sig_io);
149	schorsch	2.34	oldalrm = signal(SIGALRM, sig_alrm);
150	greg	2.2	alarm(TIMELIM);
151	greg	2.15	pflock(0); /* unlock persist file for attach */
152	greg	2.13	while (!got_io)
153	greg	2.15	pause(); /* wait for attach */
154			alarm(0); /* turn off alarm */
155	greg	2.13	signal(SIGALRM, oldalrm);
156	greg	2.2	signal(SIGIO, SIG_DFL);
157	greg	2.17	pflock(1); /* grab persist file back */
158	greg	2.1	/* someone wants us; reopen stdin and stdout */
159	greg	2.26	close(0);
160			if (open(inpname, O_RDONLY) != 0)
161			error(INTERNAL, "unexpected stdin file number");
162			clearerr(stdin);
163			close(1);
164			if (open(outpname, O_WRONLY) != 1)
165			error(INTERNAL, "unexpected stdout file number");
166	gregl	2.22	sleep(3); /* give them a chance to open their pipes */
167	greg	2.14	if (errname[0]) {
168	greg	2.26	close(2);
169			if (open(errname, O_WRONLY) != 2)
170			error(INTERNAL, "unexpected stderr file number");
171	greg	2.14	unlink(errname);
172			errname[0] = '\0';
173			}
174	greg	2.1	unlink(inpname);
175			inpname[0] = '\0';
176			unlink(outpname);
177			outpname[0] = '\0';
178			return;
179			createrr:
180			error(SYSTEM, "cannot create named pipes in pfhold");
181			}
182
183
184	greg	2.43	void
185	schorsch	2.34	io_process(void) /* just act as go-between for actual process */
186	greg	2.1	{
187	greg	2.43	char *cp;
188			int nr, n;
189	greg	2.16	char buf[BUFSIZ], pfin, pfout, *pferr;
190			int pid, nfds;
191	gregl	2.22	int fdout, fderr = -1;
192	gregl	2.23	int status = 0;
193	gregl	2.22	fd_set readfds, excepfds;
194	greg	2.15	/* load persist file */
195	greg	2.17	n = 40;
196	greg	2.15	while ((nr = read(persistfd, buf, sizeof(buf)-1)) == 0) {
197	greg	2.17	if (!n--)
198			error(USER, "unattended persist file?");
199	greg	2.15	pflock(0);
200	gregl	2.25	sleep(3+(3getpid()+random())%13); / wait until ready */
201	greg	2.15	pflock(1);
202			}
203			if (nr < 0)
204	greg	2.14	error(SYSTEM, "error reading persist file");
205	greg	2.26	ftruncate(persistfd, (off_t)0L); /* truncate persist file */
206	greg	2.17	pfdetach(); /* close & release persist file */
207			buf[nr] = '\0'; /* parse what we got */
208	schorsch	2.29	if ((cp = strchr(buf, ' ')) == NULL)
209	greg	2.1	goto formerr;
210			*cp++ = '\0';
211	greg	2.12	if ((pid = atoi(cp)) <= 0)
212	greg	2.1	goto formerr;
213	schorsch	2.29	if ((cp = strchr(cp, '\n')) == NULL)
214	greg	2.1	goto formerr;
215	greg	2.12	pfin = ++cp;
216	schorsch	2.29	if ((cp = strchr(cp, '\n')) == NULL)
217	greg	2.12	goto formerr;
218	greg	2.1	*cp++ = '\0';
219			pfout = cp;
220	schorsch	2.29	if ((cp = strchr(cp, '\n')) == NULL)
221	greg	2.1	goto formerr;
222			*cp++ = '\0';
223	greg	2.14	pferr = cp;
224	schorsch	2.29	if ((cp = strchr(cp, '\n')) == NULL)
225	greg	2.14	goto formerr;
226			*cp++ = '\0';
227	greg	2.1	if (cp-buf != nr)
228			goto formerr;
229	greg	2.12	if (strcmp(buf, progname)) {
230			sprintf(errmsg, "persist file for %s, not %s", buf, progname);
231			error(USER, errmsg);
232			}
233	greg	2.16	/* wake up rendering process */
234	greg	2.2	if (kill(pid, SIGIO) < 0)
235	greg	2.1	error(SYSTEM, "cannot signal rendering process in io_process");
236	gregl	2.22	/* fork child feeder process */
237			pid = fork();
238			if (pid < 0)
239			error(SYSTEM, "fork failed in io_process");
240			if (pid == 0) { /* feeder loop */
241			int fdin;
242			close(1); /* open input pipe */
243			if ((fdin = open(pfin, O_WRONLY)) < 0)
244			error(SYSTEM, "cannot open feed pipe in io_process");
245			/* renderer stdin */
246			while ((nr = read(0, cp=buf, sizeof(buf))) > 0) {
247			do {
248			if ((n = write(fdin, cp, nr)) <= 0)
249			goto writerr;
250			cp += n;
251			} while ((nr -= n) > 0);
252			}
253			if (nr < 0)
254			goto readerr;
255			_exit(0);
256			}
257			close(0);
258			/* open output pipes, in order */
259	greg	2.16	if ((fdout = open(pfout, O_RDONLY)) < 0)
260			error(SYSTEM, "cannot open output pipe in io_process");
261			if (pferr[0] && (fderr = open(pferr, O_RDONLY)) < 0)
262			error(SYSTEM, "cannot open error pipe in io_process");
263	gregl	2.22	for ( ; ; ) { /* eater loop */
264	greg	2.16	FD_ZERO(&readfds);
265			FD_ZERO(&excepfds);
266			nfds = 0;
267			if (fdout >= 0) {
268			FD_SET(fdout, &readfds);
269			FD_SET(fdout, &excepfds);
270			nfds = fdout+1;
271	greg	2.14	}
272	greg	2.16	if (fderr >= 0) {
273			FD_SET(fderr, &readfds);
274			FD_SET(fderr, &excepfds);
275			nfds = fderr+1;
276			}
277			if (nfds == 0)
278			break; /* all done, exit */
279	gregl	2.22	if (select(nfds, &readfds, NULL, &excepfds, NULL) < 0)
280	greg	2.16	error(SYSTEM, "error in select call in io_process");
281			/* renderer stderr */
282			if (fderr >= 0 && (FD_ISSET(fderr, &readfds) \|\|
283			FD_ISSET(fderr, &excepfds))) {
284			nr = read(fderr, cp=buf, sizeof(buf));
285			if (nr < 0)
286			goto readerr;
287			if (nr == 0) {
288			close(fderr);
289	greg	2.18	/* close(2); don't close stderr! */
290	greg	2.16	fderr = -1;
291	gregl	2.24	} else {
292	gregl	2.23	cp[nr] = '\0'; /* deduce status if we can */
293			n = strlen(progname);
294			if (!strncmp(cp, progname, n) &&
295			cp[n++] == ':' &&
296			cp[n++] == ' ') {
297	greg	2.43	struct erract *ep;
298	gregl	2.23	for (ep = erract; ep < erract+NERRS;
299			ep++)
300			if (ep->pre[0] &&
301			!strncmp(cp+n, ep->pre,
302			strlen(ep->pre))) {
303			status = ep->ec;
304			break;
305			}
306			}
307			do { /* write message */
308	greg	2.16	if ((n = write(2, cp, nr)) <= 0)
309			goto writerr;
310			cp += n;
311			} while ((nr -= n) > 0);
312	gregl	2.24	}
313	greg	2.16	}
314			/* renderer stdout */
315			if (fdout >= 0 && (FD_ISSET(fdout, &readfds) \|\|
316			FD_ISSET(fdout, &excepfds))) {
317			nr = read(fdout, cp=buf, sizeof(buf));
318			if (nr < 0)
319			goto readerr;
320			if (nr == 0) { /* EOF */
321			close(fdout);
322			close(1);
323			fdout = -1;
324			} else
325			do { /* write it all */
326			if ((n = write(1, cp, nr)) <= 0)
327			goto writerr;
328			cp += n;
329			} while ((nr -= n) > 0);
330			}
331	greg	2.1	}
332	greg	2.36	kill(pid, SIGTERM); /* no more process to feed, so... */
333	greg	2.35	waitpid(pid, 0, 0); /* wait for feeder process */
334	gregl	2.23	_exit(status);
335	greg	2.1	formerr:
336			error(USER, "format error in persist file");
337	greg	2.16	readerr:
338			error(SYSTEM, "read error in io_process");
339			writerr:
340			error(SYSTEM, "write error in io_process");
341	greg	2.1	}
342	greg	2.6
343	greg	2.8	#else
344
345	greg	2.43	void pfclean(void) {}
346	greg	2.8
347	greg	2.6	#endif