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Annotation of 43BSDReno/contrib/emacs-18.55/etc/movemail.c, revision 1.1

1.1     ! root        1: /* movemail foo bar -- move file foo to file bar,
        !             2:    locking file foo the way /bin/mail respects.
        !             3:    Copyright (C) 1986 Free Software Foundation, Inc.
        !             4: 
        !             5: This file is part of GNU Emacs.
        !             6: 
        !             7: GNU Emacs is distributed in the hope that it will be useful,
        !             8: but without any warranty.  No author or distributor
        !             9: accepts responsibility to anyone for the consequences of using it
        !            10: or for whether it serves any particular purpose or works at all,
        !            11: unless he says so in writing.
        !            12: 
        !            13: Everyone is granted permission to copy, modify and redistribute
        !            14: GNU Emacs, but only under the conditions described in the
        !            15: document "GNU Emacs copying permission notice".   An exact copy
        !            16: of the document is supposed to have been given to you along with
        !            17: GNU Emacs so that you can know how you may redistribute it all.
        !            18: It should be in a file named COPYING.  Among other things, the
        !            19: copyright notice and this notice must be preserved on all copies.  */
        !            20: 
        !            21: /*
        !            22:  * Modified January, 1986 by Michael R. Gretzinger (Project Athena)
        !            23:  *
        !            24:  * Added POP (Post Office Protocol) service.  When compiled -DPOP
        !            25:  * movemail will accept input filename arguments of the form
        !            26:  * "po:username".  This will cause movemail to open a connection to
        !            27:  * a pop server running on $MAILHOST (environment variable).  Movemail
        !            28:  * must be setuid to root in order to work with POP.
        !            29:  * 
        !            30:  * New module: popmail.c
        !            31:  * Modified routines:
        !            32:  *     main - added code within #ifdef MAIL_USE_POP; added setuid(getuid())
        !            33:  *             after POP code. 
        !            34:  * New routines in movemail.c:
        !            35:  *     get_errmsg - return pointer to system error message
        !            36:  *
        !            37:  */
        !            38: 
        !            39: #include <sys/types.h>
        !            40: #include <sys/stat.h>
        !            41: #include <sys/file.h>
        !            42: #include <errno.h>
        !            43: #define NO_SHORTNAMES   /* Tell config not to load remap.h */
        !            44: #include "../src/config.h"
        !            45: 
        !            46: #ifdef USG
        !            47: #include <fcntl.h>
        !            48: #include <unistd.h>
        !            49: #ifndef F_OK
        !            50: #define F_OK 0
        !            51: #define X_OK 1
        !            52: #define W_OK 2
        !            53: #define R_OK 4
        !            54: #endif
        !            55: #endif /* USG */
        !            56: 
        !            57: #ifdef XENIX
        !            58: #include <sys/locking.h>
        !            59: #endif
        !            60: 
        !            61: /* Cancel substitutions made by config.h for Emacs.  */
        !            62: #undef open
        !            63: #undef read
        !            64: #undef write
        !            65: #undef close
        !            66: 
        !            67: char *concat ();
        !            68: extern int errno;
        !            69: 
        !            70: /* Nonzero means this is name of a lock file to delete on fatal error.  */
        !            71: char *delete_lockname;
        !            72: 
        !            73: main (argc, argv)
        !            74:      int argc;
        !            75:      char **argv;
        !            76: {
        !            77:   char *inname, *outname;
        !            78:   int indesc, outdesc;
        !            79:   char buf[1024];
        !            80:   int nread;
        !            81: 
        !            82: #ifndef MAIL_USE_FLOCK
        !            83:   struct stat st;
        !            84:   long now;
        !            85:   int tem;
        !            86:   char *lockname, *p;
        !            87:   char tempname[40];
        !            88:   int desc;
        !            89: #endif /* not MAIL_USE_FLOCK */
        !            90: 
        !            91:   delete_lockname = 0;
        !            92: 
        !            93:   if (argc < 3)
        !            94:     fatal ("two arguments required");
        !            95: 
        !            96:   inname = argv[1];
        !            97:   outname = argv[2];
        !            98: 
        !            99:   /* Check access to input and output file.  */
        !           100:   if (access (inname, R_OK | W_OK) != 0)
        !           101:     pfatal_with_name (inname);
        !           102:   if (access (outname, F_OK) == 0 && access (outname, W_OK) != 0)
        !           103:     pfatal_with_name (outname);
        !           104: 
        !           105:   /* Also check that outname's directory is writeable to the real uid.  */
        !           106:   {
        !           107:     char *buf = (char *) malloc (strlen (outname) + 1);
        !           108:     char *p, q;
        !           109:     strcpy (buf, outname);
        !           110:     p = buf + strlen (buf);
        !           111:     while (p > buf && p[-1] != '/')
        !           112:       *--p = 0;
        !           113:     if (p == buf)
        !           114:       *p++ = '.';
        !           115:     if (access (buf, W_OK) != 0)
        !           116:       pfatal_with_name (buf);
        !           117:     free (buf);
        !           118:   }
        !           119: 
        !           120: #ifdef MAIL_USE_POP
        !           121:   if (!bcmp (inname, "po:", 3))
        !           122:     {
        !           123:       int status; char *user;
        !           124: 
        !           125:       user = (char *) rindex (inname, ':') + 1;
        !           126:       status = popmail (user, outname);
        !           127:       exit (status);
        !           128:     }
        !           129: 
        !           130:   setuid (getuid());
        !           131: #endif /* MAIL_USE_POP */
        !           132: 
        !           133: #ifndef MAIL_USE_FLOCK
        !           134:   /* Use a lock file named /usr/spool/mail/$USER.lock:
        !           135:      If it exists, the mail file is locked.  */
        !           136:   lockname = concat (inname, ".lock", "");
        !           137:   strcpy (tempname, inname);
        !           138:   p = tempname + strlen (tempname);
        !           139:   while (p != tempname && p[-1] != '/')
        !           140:     p--;
        !           141:   *p = 0;
        !           142:   strcpy (p, "EXXXXXX");
        !           143:   mktemp (tempname);
        !           144:   (void) unlink (tempname);
        !           145: 
        !           146:   while (1)
        !           147:     {
        !           148:       /* Create the lock file, but not under the lock file name.  */
        !           149:       /* Give up if cannot do that.  */
        !           150:       desc = open (tempname, O_WRONLY | O_CREAT, 0666);
        !           151:       if (desc < 0)
        !           152:         pfatal_with_name (concat ("temporary file \"", tempname, "\""));
        !           153:       close (desc);
        !           154: 
        !           155:       tem = link (tempname, lockname);
        !           156:       (void) unlink (tempname);
        !           157:       if (tem >= 0)
        !           158:        break;
        !           159:       sleep (1);
        !           160: 
        !           161:       /* If lock file is a minute old, unlock it.  */
        !           162:       if (stat (lockname, &st) >= 0)
        !           163:        {
        !           164:          now = time (0);
        !           165:          if (st.st_ctime < now - 60)
        !           166:            (void) unlink (lockname);
        !           167:        }
        !           168:     }
        !           169: 
        !           170:   delete_lockname = lockname;
        !           171: #endif /* not MAIL_USE_FLOCK */
        !           172: 
        !           173: #ifdef MAIL_USE_FLOCK
        !           174:   indesc = open (inname, O_RDWR);
        !           175: #else /* if not MAIL_USE_FLOCK */
        !           176:   indesc = open (inname, O_RDONLY);
        !           177: #endif /* not MAIL_USE_FLOCK */
        !           178:   if (indesc < 0)
        !           179:     pfatal_with_name (inname);
        !           180: 
        !           181: #if defined(BSD) || defined(XENIX)
        !           182:   /* In case movemail is setuid to root, make sure the user can
        !           183:      read the output file.  */
        !           184:   /* This is desirable for all systems
        !           185:      but I don't want to assume all have the umask system call */
        !           186:   umask (umask (0) & 0333);
        !           187: #endif /* BSD or Xenix */
        !           188:   outdesc = open (outname, O_WRONLY | O_CREAT | O_EXCL, 0666);
        !           189:   if (outdesc < 0)
        !           190:     pfatal_with_name (outname);
        !           191: #ifdef MAIL_USE_FLOCK
        !           192: #ifdef XENIX
        !           193:   if (locking (indesc, LK_RLCK, 0L) < 0) pfatal_with_name (inname);
        !           194: #else
        !           195:   flock (indesc, LOCK_EX);
        !           196: #endif
        !           197: #endif /* MAIL_USE_FLOCK */
        !           198: 
        !           199:   while (1)
        !           200:     {
        !           201:       nread = read (indesc, buf, sizeof buf);
        !           202:       if (nread != write (outdesc, buf, nread))
        !           203:        {
        !           204:          int saved_errno = errno;
        !           205:          (void) unlink (outname);
        !           206:          errno = saved_errno;
        !           207:          pfatal_with_name (outname);
        !           208:        }
        !           209:       if (nread < sizeof buf)
        !           210:        break;
        !           211:     }
        !           212: 
        !           213: #ifdef BSD
        !           214:   fsync (outdesc);
        !           215: #endif
        !           216: 
        !           217:   /* Check to make sure no errors before we zap the inbox.  */
        !           218:   if (close (outdesc) != 0)
        !           219:     {
        !           220:       int saved_errno = errno;
        !           221:       (void) unlink (outname);
        !           222:       errno = saved_errno;
        !           223:       pfatal_with_name (outname);
        !           224:   }
        !           225: 
        !           226: #ifdef MAIL_USE_FLOCK
        !           227: #if defined(STRIDE) || defined(XENIX)
        !           228:   /* Stride, xenix have file locking, but no ftruncate.  This mess will do. */
        !           229:   (void) close (open (inname, O_CREAT | O_TRUNC | O_RDWR, 0666));
        !           230: #else
        !           231:   (void) ftruncate (indesc, 0L);
        !           232: #endif /* STRIDE or XENIX */
        !           233: #endif /* MAIL_USE_FLOCK */
        !           234:   close (indesc);
        !           235: 
        !           236: #ifndef MAIL_USE_FLOCK
        !           237:   /* Delete the input file; if we can't, at least get rid of its contents.  */
        !           238:   if (unlink (inname) < 0)
        !           239:     if (errno != ENOENT)
        !           240:       creat (inname, 0666);
        !           241:   (void) unlink (lockname);
        !           242: #endif /* not MAIL_USE_FLOCK */
        !           243:   exit (0);
        !           244: }
        !           245: 
        !           246: /* Print error message and exit.  */
        !           247: 
        !           248: fatal (s1, s2)
        !           249:      char *s1, *s2;
        !           250: {
        !           251:   if (delete_lockname)
        !           252:     unlink (delete_lockname);
        !           253:   error (s1, s2);
        !           254:   exit (1);
        !           255: }
        !           256: 
        !           257: /* Print error message.  `s1' is printf control string, `s2' is arg for it. */
        !           258: 
        !           259: error (s1, s2)
        !           260:      char *s1, *s2;
        !           261: {
        !           262:   printf ("movemail: ");
        !           263:   printf (s1, s2);
        !           264:   printf ("\n");
        !           265: }
        !           266: 
        !           267: pfatal_with_name (name)
        !           268:      char *name;
        !           269: {
        !           270:   extern int errno, sys_nerr;
        !           271:   extern char *sys_errlist[];
        !           272:   char *s;
        !           273: 
        !           274:   if (errno < sys_nerr)
        !           275:     s = concat ("", sys_errlist[errno], " for %s");
        !           276:   else
        !           277:     s = "cannot open %s";
        !           278:   fatal (s, name);
        !           279: }
        !           280: 
        !           281: /* Return a newly-allocated string whose contents concatenate those of s1, s2, s3.  */
        !           282: 
        !           283: char *
        !           284: concat (s1, s2, s3)
        !           285:      char *s1, *s2, *s3;
        !           286: {
        !           287:   int len1 = strlen (s1), len2 = strlen (s2), len3 = strlen (s3);
        !           288:   char *result = (char *) xmalloc (len1 + len2 + len3 + 1);
        !           289: 
        !           290:   strcpy (result, s1);
        !           291:   strcpy (result + len1, s2);
        !           292:   strcpy (result + len1 + len2, s3);
        !           293:   *(result + len1 + len2 + len3) = 0;
        !           294: 
        !           295:   return result;
        !           296: }
        !           297: 
        !           298: /* Like malloc but get fatal error if memory is exhausted.  */
        !           299: 
        !           300: int
        !           301: xmalloc (size)
        !           302:      int size;
        !           303: {
        !           304:   int result = malloc (size);
        !           305:   if (!result)
        !           306:     fatal ("virtual memory exhausted", 0);
        !           307:   return result;
        !           308: }
        !           309: 
        !           310: /* This is the guts of the interface to the Post Office Protocol.  */
        !           311: 
        !           312: #ifdef MAIL_USE_POP
        !           313: 
        !           314: #include <sys/socket.h>
        !           315: #include <netinet/in.h>
        !           316: #include <netdb.h>
        !           317: #include <stdio.h>
        !           318: 
        !           319: #ifdef USG
        !           320: #include <fcntl.h>
        !           321: /* Cancel substitutions made by config.h for Emacs.  */
        !           322: #undef open
        !           323: #undef read
        !           324: #undef write
        !           325: #undef close
        !           326: #endif /* USG */
        !           327: 
        !           328: #define NOTOK (-1)
        !           329: #define OK 0
        !           330: #define DONE 1
        !           331: 
        !           332: char *progname;
        !           333: FILE *sfi;
        !           334: FILE *sfo;
        !           335: char Errmsg[80];
        !           336: 
        !           337: static int debug = 0;
        !           338: 
        !           339: popmail(user, outfile)
        !           340: char *user;
        !           341: char *outfile;
        !           342: {
        !           343:     char *host;
        !           344:     int nmsgs, nbytes;
        !           345:     char response[128];
        !           346:     register int i;
        !           347:     int mbfi;
        !           348:     FILE *mbf;
        !           349:     char *getenv();
        !           350:     int mbx_write();
        !           351:     char *get_errmsg();
        !           352: 
        !           353:     host = getenv("MAILHOST");
        !           354:     if (host == NULL) {
        !           355:        fatal("no MAILHOST defined");
        !           356:     }
        !           357: 
        !           358:     if (pop_init(host) == NOTOK) {
        !           359:        error(Errmsg);
        !           360:        return(1);
        !           361:     }
        !           362: 
        !           363:     if (getline(response, sizeof response, sfi) != OK) {
        !           364:        error(response);
        !           365:        return(1);
        !           366:     }
        !           367: 
        !           368:     if (pop_command("USER %s", user) == NOTOK || 
        !           369:        pop_command("RPOP %s", user) == NOTOK) {
        !           370:        error(Errmsg);
        !           371:        pop_command("QUIT");
        !           372:        return(1);
        !           373:     }
        !           374: 
        !           375:     if (pop_stat(&nmsgs, &nbytes) == NOTOK) {
        !           376:        error(Errmsg);
        !           377:        pop_command("QUIT");
        !           378:        return(1);
        !           379:     }
        !           380: 
        !           381:     if (!nmsgs)
        !           382:       {
        !           383:        pop_command("QUIT");
        !           384:        return(0);
        !           385:       }
        !           386: 
        !           387:     mbfi = open (outfile, O_WRONLY | O_CREAT | O_EXCL, 0666);
        !           388:     if (mbfi < 0)
        !           389:       {
        !           390:        pop_command("QUIT");
        !           391:        error("Error in open: %s, %s", get_errmsg(), outfile);
        !           392:        return(1);
        !           393:       }
        !           394:     fchown(mbfi, getuid(), -1);
        !           395: 
        !           396:     if ((mbf = fdopen(mbfi, "w")) == NULL)
        !           397:       {
        !           398:        pop_command("QUIT");
        !           399:        error("Error in fdopen: %s", get_errmsg());
        !           400:        close(mbfi);
        !           401:        unlink(outfile);
        !           402:        return(1);
        !           403:       }
        !           404: 
        !           405:     for (i = 1; i <= nmsgs; i++) {
        !           406:        mbx_delimit_begin(mbf);
        !           407:        if (pop_retr(i, mbx_write, mbf) != OK) {
        !           408:            error(Errmsg);
        !           409:            pop_command("QUIT");
        !           410:            close(mbfi);
        !           411:            return(1);
        !           412:        }
        !           413:        mbx_delimit_end(mbf);
        !           414:        fflush(mbf);
        !           415:     }
        !           416: 
        !           417:     for (i = 1; i <= nmsgs; i++) {
        !           418:        if (pop_command("DELE %d", i) == NOTOK) {
        !           419:            error(Errmsg);
        !           420:            pop_command("QUIT");
        !           421:            close(mbfi);
        !           422:            return(1);
        !           423:        }
        !           424:     }
        !           425: 
        !           426:     pop_command("QUIT");
        !           427:     close(mbfi);
        !           428:     return(0);
        !           429: }
        !           430: 
        !           431: pop_init(host)
        !           432: char *host;
        !           433: {
        !           434:     register struct hostent *hp;
        !           435:     register struct servent *sp;
        !           436:     int lport = IPPORT_RESERVED - 1;
        !           437:     struct sockaddr_in sin;
        !           438:     register int s;
        !           439:     char *get_errmsg();
        !           440: 
        !           441:     hp = gethostbyname(host);
        !           442:     if (hp == NULL) {
        !           443:        sprintf(Errmsg, "MAILHOST unknown: %s", host);
        !           444:        return(NOTOK);
        !           445:     }
        !           446: 
        !           447:     sp = getservbyname("pop", "tcp");
        !           448:     if (sp == 0) {
        !           449:        strcpy(Errmsg, "tcp/pop: unknown service");
        !           450:        return(NOTOK);
        !           451:     }
        !           452: 
        !           453:     sin.sin_family = hp->h_addrtype;
        !           454:     bcopy(hp->h_addr, (char *)&sin.sin_addr, hp->h_length);
        !           455:     sin.sin_port = sp->s_port;
        !           456:     s = rresvport(&lport);
        !           457:     if (s < 0) {
        !           458:        sprintf(Errmsg, "error creating socket: %s", get_errmsg());
        !           459:        return(NOTOK);
        !           460:     }
        !           461: 
        !           462:     if (connect(s, (char *)&sin, sizeof sin) < 0) {
        !           463:        sprintf(Errmsg, "error during connect: %s", get_errmsg());
        !           464:        close(s);
        !           465:        return(NOTOK);
        !           466:     }
        !           467: 
        !           468:     sfi = fdopen(s, "r");
        !           469:     sfo = fdopen(s, "w");
        !           470:     if (sfi == NULL || sfo == NULL) {
        !           471:        sprintf(Errmsg, "error in fdopen: %s", get_errmsg());
        !           472:        close(s);
        !           473:        return(NOTOK);
        !           474:     }
        !           475: 
        !           476:     return(OK);
        !           477: }
        !           478: 
        !           479: pop_command(fmt, a, b, c, d)
        !           480: char *fmt;
        !           481: {
        !           482:     char buf[128];
        !           483:     char errmsg[64];
        !           484: 
        !           485:     sprintf(buf, fmt, a, b, c, d);
        !           486: 
        !           487:     if (debug) fprintf(stderr, "---> %s\n", buf);
        !           488:     if (putline(buf, Errmsg, sfo) == NOTOK) return(NOTOK);
        !           489: 
        !           490:     if (getline(buf, sizeof buf, sfi) != OK) {
        !           491:        strcpy(Errmsg, buf);
        !           492:        return(NOTOK);
        !           493:     }
        !           494: 
        !           495:     if (debug) fprintf(stderr, "<--- %s\n", buf);
        !           496:     if (*buf != '+') {
        !           497:        strcpy(Errmsg, buf);
        !           498:        return(NOTOK);
        !           499:     } else {
        !           500:        return(OK);
        !           501:     }
        !           502: }
        !           503: 
        !           504:     
        !           505: pop_stat(nmsgs, nbytes)
        !           506: int *nmsgs, *nbytes;
        !           507: {
        !           508:     char buf[128];
        !           509: 
        !           510:     if (debug) fprintf(stderr, "---> STAT\n");
        !           511:     if (putline("STAT", Errmsg, sfo) == NOTOK) return(NOTOK);
        !           512: 
        !           513:     if (getline(buf, sizeof buf, sfi) != OK) {
        !           514:        strcpy(Errmsg, buf);
        !           515:        return(NOTOK);
        !           516:     }
        !           517: 
        !           518:     if (debug) fprintf(stderr, "<--- %s\n", buf);
        !           519:     if (*buf != '+') {
        !           520:        strcpy(Errmsg, buf);
        !           521:        return(NOTOK);
        !           522:     } else {
        !           523:        sscanf(buf, "+OK %d %d", nmsgs, nbytes);
        !           524:        return(OK);
        !           525:     }
        !           526: }
        !           527: 
        !           528: pop_retr(msgno, action, arg)
        !           529: int (*action)();
        !           530: {
        !           531:     char buf[128];
        !           532: 
        !           533:     sprintf(buf, "RETR %d", msgno);
        !           534:     if (debug) fprintf(stderr, "%s\n", buf);
        !           535:     if (putline(buf, Errmsg, sfo) == NOTOK) return(NOTOK);
        !           536: 
        !           537:     if (getline(buf, sizeof buf, sfi) != OK) {
        !           538:        strcpy(Errmsg, buf);
        !           539:        return(NOTOK);
        !           540:     }
        !           541: 
        !           542:     while (1) {
        !           543:        switch (multiline(buf, sizeof buf, sfi)) {
        !           544:        case OK:
        !           545:            (*action)(buf, arg);
        !           546:            break;
        !           547:        case DONE:
        !           548:            return (OK);
        !           549:        case NOTOK:
        !           550:            strcpy(Errmsg, buf);
        !           551:            return (NOTOK);
        !           552:        }
        !           553:     }
        !           554: }
        !           555: 
        !           556: getline(buf, n, f)
        !           557: char *buf;
        !           558: register int n;
        !           559: FILE *f;
        !           560: {
        !           561:     register char *p;
        !           562:     int c;
        !           563: 
        !           564:     p = buf;
        !           565:     while (--n > 0 && (c = fgetc(f)) != EOF)
        !           566:       if ((*p++ = c) == '\n') break;
        !           567: 
        !           568:     if (ferror(f)) {
        !           569:        strcpy(buf, "error on connection");
        !           570:        return (NOTOK);
        !           571:     }
        !           572: 
        !           573:     if (c == EOF && p == buf) {
        !           574:        strcpy(buf, "connection closed by foreign host");
        !           575:        return (DONE);
        !           576:     }
        !           577: 
        !           578:     *p = NULL;
        !           579:     if (*--p == '\n') *p = NULL;
        !           580:     if (*--p == '\r') *p = NULL;
        !           581:     return(OK);
        !           582: }
        !           583: 
        !           584: multiline(buf, n, f)
        !           585: char *buf;
        !           586: register int n;
        !           587: FILE *f;
        !           588: {
        !           589:     if (getline(buf, n, f) != OK) return (NOTOK);
        !           590:     if (*buf == '.') {
        !           591:        if (*(buf+1) == NULL) {
        !           592:            return (DONE);
        !           593:        } else {
        !           594:            strcpy(buf, buf+1);
        !           595:        }
        !           596:     }
        !           597:     return(OK);
        !           598: }
        !           599: 
        !           600: char *
        !           601: get_errmsg()
        !           602: {
        !           603:     extern int errno, sys_nerr;
        !           604:     extern char *sys_errlist[];
        !           605:     char *s;
        !           606: 
        !           607:     if (errno < sys_nerr)
        !           608:       s = sys_errlist[errno];
        !           609:     else
        !           610:       s = "unknown error";
        !           611:     return(s);
        !           612: }
        !           613: 
        !           614: putline(buf, err, f)
        !           615: char *buf;
        !           616: char *err;
        !           617: FILE *f;
        !           618: {
        !           619:     fprintf(f, "%s\r\n", buf);
        !           620:     fflush(f);
        !           621:     if (ferror(f)) {
        !           622:        strcpy(err, "lost connection");
        !           623:        return(NOTOK);
        !           624:     }
        !           625:     return(OK);
        !           626: }
        !           627: 
        !           628: mbx_write(line, mbf)
        !           629: char *line;
        !           630: FILE *mbf;
        !           631: {
        !           632:     fputs(line, mbf);
        !           633:     fputc(0x0a, mbf);
        !           634: }
        !           635: 
        !           636: mbx_delimit_begin(mbf)
        !           637: FILE *mbf;
        !           638: {
        !           639:     fputs("\f\n0,unseen,,\n", mbf);
        !           640: }
        !           641: 
        !           642: mbx_delimit_end(mbf)
        !           643: FILE *mbf;
        !           644: {
        !           645:     putc('\037', mbf);
        !           646: }
        !           647: 
        !           648: #endif /* MAIL_USE_POP */

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