src/rt/persist.c

#ifndef lint
static const char       RCSid[] = "$Id: persist.c,v 2.39 2008/04/21 07:31:30 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 "paths.h"
#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 (sighandler_t)(int);
static sighandler_t sig_io;
static sighandler_t sig_alrm;


extern 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;
}


extern 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);
}


extern 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");
}


extern 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); }


extern void
pfhold(void)            /* holding pattern for idle rendering process */
{
        sighandler_t    *oldalrm;
        char    buf[512];
        register 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 */
        /*
        if (freopen(inpname, "r", stdin) == NULL)
                goto openerr;
        if (freopen(outpname, "w", stdout) == NULL)
                goto openerr;
        */
        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");
openerr:
        error(SYSTEM, "cannot open named pipes in pfhold");
}


extern void
io_process(void)                /* just act as go-between for actual process */
{
        register char   *cp;
        register 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");
#ifndef _WIN32 /* XXX we need a replacement for that one */
        ftruncate(persistfd, (off_t)0L);        /* truncate persist file */
#endif
        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++] == ' ') {
                                        register 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

extern void pfclean(void) {}

#endif
Revision:	2.40
Committed:	Sun Apr 27 17:22:49 2008 UTC (17 years, 6 months ago) by schorsch
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rad3R9
Changes since 2.39:	+3 -2 lines
Log Message:	Yet some mingw related changes.
#	User	Rev	Content
1	greg	2.1	#ifndef lint
2	schorsch	2.40	static const char RCSid[] = "$Id: persist.c,v 2.39 2008/04/21 07:31:30 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	greg	2.1	#include "paths.h"
29	gregl	2.21	#include "selcall.h"
30	greg	2.1
31	greg	2.2	#ifndef TIMELIM
32			#define TIMELIM (83600) / time limit for holding pattern */
33	greg	2.26	#endif
34
35	greg	2.1	extern int headismine; /* boolean true if header belongs to me */
36	greg	2.12	extern char progname; / global program name */
37	greg	2.14	extern char errfile; / global error file name */
38	greg	2.1	static char persistfname = NULL; / persist file name */
39			static int persistfd = -1; /* persist file descriptor */
40	schorsch	2.34	static char inpname[TEMPLEN+1], outpname[TEMPLEN+1], errname[TEMPLEN+1];
41	greg	2.1
42	schorsch	2.34	typedef void (sighandler_t)(int);
43			static sighandler_t sig_io;
44			static sighandler_t sig_alrm;
45	greg	2.1
46
47	schorsch	2.34	extern void
48			pfdetach(void) /* release persist (and header) resources */
49	greg	2.1	{
50			if (persistfd >= 0)
51			close(persistfd);
52			persistfd = -1;
53			persistfname = NULL;
54			inpname[0] = '\0';
55			outpname[0] = '\0';
56	greg	2.14	errname[0] = '\0';
57	greg	2.1	headismine = 0;
58			}
59
60
61	schorsch	2.34	extern void
62			pfclean(void) /* clean up persist files */
63	greg	2.1	{
64			if (persistfd >= 0)
65			close(persistfd);
66			if (persistfname != NULL)
67			unlink(persistfname);
68			if (inpname[0])
69			unlink(inpname);
70			if (outpname[0])
71			unlink(outpname);
72	greg	2.14	if (errname[0])
73			unlink(errname);
74	greg	2.1	}
75
76
77	schorsch	2.34	extern void
78			pflock( /* place or release exclusive lock on file */
79			int lf
80			)
81	greg	2.1	{
82			struct flock fls;
83
84			fls.l_type = lf ? F_WRLCK : F_UNLCK;
85			fls.l_whence = 0;
86			fls.l_start = 0L;
87			fls.l_len = 0L;
88			if (fcntl(persistfd, F_SETLKW, &fls) < 0)
89			error(SYSTEM, "cannot (un)lock persist file");
90			}
91
92
93	schorsch	2.34	extern void
94			persistfile( /* open persist file and lock it */
95			char *pfn
96			)
97	greg	2.1	{
98	greg	2.13	persistfd = open(pfn, O_WRONLY\|O_CREAT\|O_EXCL, 0644);
99	greg	2.1	if (persistfd >= 0) {
100			persistfname = pfn;
101			pflock(1);
102			return;
103			}
104			/* file exists -- switch to i/o process */
105			persistfd = open(pfn, O_RDWR);
106			if (persistfd < 0) {
107			sprintf(errmsg, "cannot open persist file \"%s\"", pfn);
108			error(SYSTEM, errmsg);
109			}
110			pflock(1);
111			io_process(); /* never returns */
112			}
113
114
115	greg	2.13	static int got_io;
116	greg	2.1
117	schorsch	2.34	static void sig_io(int i) { got_io++; }
118	greg	2.1
119	schorsch	2.34	static void sig_alrm(int i) { quit(0); }
120	greg	2.13
121
122	schorsch	2.34	extern void
123			pfhold(void) /* holding pattern for idle rendering process */
124	greg	2.1	{
125	schorsch	2.34	sighandler_t *oldalrm;
126	greg	2.12	char buf[512];
127	greg	2.1	register int n;
128			/* close input and output descriptors */
129	greg	2.37	close(0);
130			close(1);
131	greg	2.16	if (errfile == NULL)
132	greg	2.37	close(2);
133	greg	2.1	/* create named pipes for input and output */
134	greg	2.26	if (mkfifo(mktemp(strcpy(inpname,TEMPLATE)), 0600) < 0)
135	greg	2.1	goto createrr;
136	greg	2.26	if (mkfifo(mktemp(strcpy(outpname,TEMPLATE)), 0600) < 0)
137	greg	2.1	goto createrr;
138	greg	2.14	if (errfile == NULL &&
139	greg	2.26	mkfifo(mktemp(strcpy(errname,TEMPLATE)), 0600) < 0)
140	greg	2.14	goto createrr;
141			sprintf(buf, "%s %d\n%s\n%s\n%s\n", progname, getpid(),
142			inpname, outpname, errname);
143	greg	2.1	n = strlen(buf);
144			if (write(persistfd, buf, n) < n)
145	greg	2.10	error(SYSTEM, "error writing persist file");
146	greg	2.32	lseek(persistfd, (off_t)0, SEEK_SET);
147	greg	2.2	/* wait TIMELIM for someone to signal us */
148	greg	2.13	got_io = 0;
149			signal(SIGIO, sig_io);
150	schorsch	2.34	oldalrm = signal(SIGALRM, sig_alrm);
151	greg	2.2	alarm(TIMELIM);
152	greg	2.15	pflock(0); /* unlock persist file for attach */
153	greg	2.13	while (!got_io)
154	greg	2.15	pause(); /* wait for attach */
155			alarm(0); /* turn off alarm */
156	greg	2.13	signal(SIGALRM, oldalrm);
157	greg	2.2	signal(SIGIO, SIG_DFL);
158	greg	2.17	pflock(1); /* grab persist file back */
159	greg	2.1	/* someone wants us; reopen stdin and stdout */
160	greg	2.26	/*
161	greg	2.1	if (freopen(inpname, "r", stdin) == NULL)
162			goto openerr;
163			if (freopen(outpname, "w", stdout) == NULL)
164			goto openerr;
165	greg	2.26	*/
166			close(0);
167			if (open(inpname, O_RDONLY) != 0)
168			error(INTERNAL, "unexpected stdin file number");
169			clearerr(stdin);
170			close(1);
171			if (open(outpname, O_WRONLY) != 1)
172			error(INTERNAL, "unexpected stdout file number");
173	gregl	2.22	sleep(3); /* give them a chance to open their pipes */
174	greg	2.14	if (errname[0]) {
175	greg	2.26	close(2);
176			if (open(errname, O_WRONLY) != 2)
177			error(INTERNAL, "unexpected stderr file number");
178	greg	2.14	unlink(errname);
179			errname[0] = '\0';
180			}
181	greg	2.1	unlink(inpname);
182			inpname[0] = '\0';
183			unlink(outpname);
184			outpname[0] = '\0';
185			return;
186			createrr:
187			error(SYSTEM, "cannot create named pipes in pfhold");
188			openerr:
189			error(SYSTEM, "cannot open named pipes in pfhold");
190			}
191
192
193	schorsch	2.34	extern void
194			io_process(void) /* just act as go-between for actual process */
195	greg	2.1	{
196			register char *cp;
197			register int nr, n;
198	greg	2.16	char buf[BUFSIZ], pfin, pfout, *pferr;
199			int pid, nfds;
200	gregl	2.22	int fdout, fderr = -1;
201	gregl	2.23	int status = 0;
202	gregl	2.22	fd_set readfds, excepfds;
203	greg	2.15	/* load persist file */
204	greg	2.17	n = 40;
205	greg	2.15	while ((nr = read(persistfd, buf, sizeof(buf)-1)) == 0) {
206	greg	2.17	if (!n--)
207			error(USER, "unattended persist file?");
208	greg	2.15	pflock(0);
209	gregl	2.25	sleep(3+(3getpid()+random())%13); / wait until ready */
210	greg	2.15	pflock(1);
211			}
212			if (nr < 0)
213	greg	2.14	error(SYSTEM, "error reading persist file");
214	schorsch	2.28	#ifndef _WIN32 /* XXX we need a replacement for that one */
215	greg	2.26	ftruncate(persistfd, (off_t)0L); /* truncate persist file */
216	schorsch	2.28	#endif
217	greg	2.17	pfdetach(); /* close & release persist file */
218			buf[nr] = '\0'; /* parse what we got */
219	schorsch	2.29	if ((cp = strchr(buf, ' ')) == NULL)
220	greg	2.1	goto formerr;
221			*cp++ = '\0';
222	greg	2.12	if ((pid = atoi(cp)) <= 0)
223	greg	2.1	goto formerr;
224	schorsch	2.29	if ((cp = strchr(cp, '\n')) == NULL)
225	greg	2.1	goto formerr;
226	greg	2.12	pfin = ++cp;
227	schorsch	2.29	if ((cp = strchr(cp, '\n')) == NULL)
228	greg	2.12	goto formerr;
229	greg	2.1	*cp++ = '\0';
230			pfout = cp;
231	schorsch	2.29	if ((cp = strchr(cp, '\n')) == NULL)
232	greg	2.1	goto formerr;
233			*cp++ = '\0';
234	greg	2.14	pferr = cp;
235	schorsch	2.29	if ((cp = strchr(cp, '\n')) == NULL)
236	greg	2.14	goto formerr;
237			*cp++ = '\0';
238	greg	2.1	if (cp-buf != nr)
239			goto formerr;
240	greg	2.12	if (strcmp(buf, progname)) {
241			sprintf(errmsg, "persist file for %s, not %s", buf, progname);
242			error(USER, errmsg);
243			}
244	greg	2.16	/* wake up rendering process */
245	greg	2.2	if (kill(pid, SIGIO) < 0)
246	greg	2.1	error(SYSTEM, "cannot signal rendering process in io_process");
247	gregl	2.22	/* fork child feeder process */
248			pid = fork();
249			if (pid < 0)
250			error(SYSTEM, "fork failed in io_process");
251			if (pid == 0) { /* feeder loop */
252			int fdin;
253			close(1); /* open input pipe */
254			if ((fdin = open(pfin, O_WRONLY)) < 0)
255			error(SYSTEM, "cannot open feed pipe in io_process");
256			/* renderer stdin */
257			while ((nr = read(0, cp=buf, sizeof(buf))) > 0) {
258			do {
259			if ((n = write(fdin, cp, nr)) <= 0)
260			goto writerr;
261			cp += n;
262			} while ((nr -= n) > 0);
263			}
264			if (nr < 0)
265			goto readerr;
266			_exit(0);
267			}
268			close(0);
269			/* open output pipes, in order */
270	greg	2.16	if ((fdout = open(pfout, O_RDONLY)) < 0)
271			error(SYSTEM, "cannot open output pipe in io_process");
272			if (pferr[0] && (fderr = open(pferr, O_RDONLY)) < 0)
273			error(SYSTEM, "cannot open error pipe in io_process");
274	gregl	2.22	for ( ; ; ) { /* eater loop */
275	greg	2.16	FD_ZERO(&readfds);
276			FD_ZERO(&excepfds);
277			nfds = 0;
278			if (fdout >= 0) {
279			FD_SET(fdout, &readfds);
280			FD_SET(fdout, &excepfds);
281			nfds = fdout+1;
282	greg	2.14	}
283	greg	2.16	if (fderr >= 0) {
284			FD_SET(fderr, &readfds);
285			FD_SET(fderr, &excepfds);
286			nfds = fderr+1;
287			}
288			if (nfds == 0)
289			break; /* all done, exit */
290	gregl	2.22	if (select(nfds, &readfds, NULL, &excepfds, NULL) < 0)
291	greg	2.16	error(SYSTEM, "error in select call in io_process");
292			/* renderer stderr */
293			if (fderr >= 0 && (FD_ISSET(fderr, &readfds) \|\|
294			FD_ISSET(fderr, &excepfds))) {
295			nr = read(fderr, cp=buf, sizeof(buf));
296			if (nr < 0)
297			goto readerr;
298			if (nr == 0) {
299			close(fderr);
300	greg	2.18	/* close(2); don't close stderr! */
301	greg	2.16	fderr = -1;
302	gregl	2.24	} else {
303	gregl	2.23	cp[nr] = '\0'; /* deduce status if we can */
304			n = strlen(progname);
305			if (!strncmp(cp, progname, n) &&
306			cp[n++] == ':' &&
307			cp[n++] == ' ') {
308			register struct erract *ep;
309			for (ep = erract; ep < erract+NERRS;
310			ep++)
311			if (ep->pre[0] &&
312			!strncmp(cp+n, ep->pre,
313			strlen(ep->pre))) {
314			status = ep->ec;
315			break;
316			}
317			}
318			do { /* write message */
319	greg	2.16	if ((n = write(2, cp, nr)) <= 0)
320			goto writerr;
321			cp += n;
322			} while ((nr -= n) > 0);
323	gregl	2.24	}
324	greg	2.16	}
325			/* renderer stdout */
326			if (fdout >= 0 && (FD_ISSET(fdout, &readfds) \|\|
327			FD_ISSET(fdout, &excepfds))) {
328			nr = read(fdout, cp=buf, sizeof(buf));
329			if (nr < 0)
330			goto readerr;
331			if (nr == 0) { /* EOF */
332			close(fdout);
333			close(1);
334			fdout = -1;
335			} else
336			do { /* write it all */
337			if ((n = write(1, cp, nr)) <= 0)
338			goto writerr;
339			cp += n;
340			} while ((nr -= n) > 0);
341			}
342	greg	2.1	}
343	greg	2.36	kill(pid, SIGTERM); /* no more process to feed, so... */
344	greg	2.35	waitpid(pid, 0, 0); /* wait for feeder process */
345	gregl	2.23	_exit(status);
346	greg	2.1	formerr:
347			error(USER, "format error in persist file");
348	greg	2.16	readerr:
349			error(SYSTEM, "read error in io_process");
350			writerr:
351			error(SYSTEM, "write error in io_process");
352	greg	2.1	}
353	greg	2.6
354	greg	2.8	#else
355
356	schorsch	2.34	extern void pfclean(void) {}
357	greg	2.8
358	greg	2.6	#endif