/*      $OpenBSD: printjob.c,v 1.62 2021/10/24 21:24:18 deraadt Exp $   */
/*      $NetBSD: printjob.c,v 1.31 2002/01/21 14:42:30 wiz Exp $        */

/*
 * Copyright (c) 1983, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 */

/*
 * printjob -- print jobs in the queue.
 *
 *      NOTE: the lock file is used to pass information to lpq and lprm.
 *      it does not need to be removed because file locks are dynamic.
 */

#include <sys/types.h>
#include <sys/wait.h>
#include <sys/stat.h>

#include <pwd.h>
#include <unistd.h>
#include <signal.h>
#include <termios.h>
#include <syslog.h>
#include <fcntl.h>
#include <dirent.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <limits.h>
#include <stdlib.h>
#include <stdarg.h>
#include <ctype.h>

#include "lp.h"
#include "lp.local.h"
#include "pathnames.h"
#include "extern.h"

#define DORETURN        0       /* absorb fork error */
#define DOABORT         1       /* abort if dofork fails */

/*
 * Error tokens
 */
#define REPRINT         -2
#define ERROR           -1
#define OK              0
#define FATALERR        1
#define NOACCT          2
#define FILTERERR       3
#define ACCESS          4

static dev_t     fdev;          /* device of file pointed to by symlink */
static ino_t     fino;          /* inode of file pointed to by symlink */
static FILE     *cfp;           /* control file */
static pid_t     child;         /* pid of any filters */
static int       lfd;           /* lock file descriptor */
static int       ofd;           /* output filter file descriptor */
static pid_t     ofilter;       /* pid of output filter, if any */
static int       pfd;           /* prstatic inter file descriptor */
static pid_t     pid;           /* pid of lpd process */
static pid_t     prchild;       /* pid of pr process */
static char      title[80];     /* ``pr'' title */
static int       tof;           /* true if at top of form */

static char     class[32];              /* classification field */
static char     fromhost[HOST_NAME_MAX+1]; /* user's host machine */
                                /* indentation size in static characters */
static char     indent[10] = "-i0";
static char     jobname[NAME_MAX];      /* job or file name */
static char     length[10] = "-l";      /* page length in lines */
static char     logname[LOGIN_NAME_MAX];/* user's login name */
static char     pxlength[10] = "-y";    /* page length in pixels */
static char     pxwidth[10] = "-x";     /* page width in pixels */
static char     tempfile[] = "errsXXXXXXXXXX"; /* file name for filter output */
static char     width[10] = "-w";       /* page width in static characters */

static void       abortpr(int);
static void       banner(char *, char *);
static void       delay(int);
static pid_t      dofork(int);
static int        dropit(int);
static void       init(void);
static void       openpr(void);
static void       opennet(char *);
static void       opentty(void);
static void       openrem(void);
static int        print(int, char *);
static int        printit(char *);
static void       pstatus(const char *, ...)
        __attribute__((__format__(__printf__, 1, 2)));
static char       response(void);
static void       scan_out(int, char *, int);
static char      *scnline(int, char *, int);
static int        sendfile(int, char *);
static int        sendit(char *);
static void       sendmail(char *, int);
static void       setty(void);
static void       alarmer(int);

void
printjob(void)
{
        struct stat stb;
        struct queue *q, **qp;
        struct queue **queue;
        struct sigaction sa;
        int i, fd, nitems;
        off_t pidoff;
        int errcnt, count = 0;

        init();                                 /* set up capabilities */
        (void)write(STDOUT_FILENO, "", 1);      /* ack that daemon is started */
        PRIV_START;
        fd = open(LF, O_WRONLY|O_APPEND);       /* set up log file */
        PRIV_END;
        if (fd < 0) {
                syslog(LOG_ERR, "%s: %m", LF);
                if ((fd = open(_PATH_DEVNULL, O_WRONLY)) < 0)
                        exit(1);
        }
        if (fd != STDERR_FILENO) {
                if (dup2(fd, STDERR_FILENO) < 0) {
                        syslog(LOG_ERR, "dup2: %m");
                        exit(1);
                }
                (void)close(fd);
        }
        setpgid(0, 0);

        /* we add SIGINT to the mask so abortpr() doesn't kill itself */
        memset(&sa, 0, sizeof(sa));
        sa.sa_handler = abortpr;
        sa.sa_flags = SA_RESTART;
        sigemptyset(&sa.sa_mask);
        sigaddset(&sa.sa_mask, SIGINT);
        sigaction(SIGHUP, &sa, NULL);
        sigaction(SIGINT, &sa, NULL);
        sigaction(SIGQUIT, &sa, NULL);
        sigaction(SIGTERM, &sa, NULL);

        /* so we can use short form file names */
        if (chdir(SD) < 0) {
                syslog(LOG_ERR, "%s: %m", SD);
                exit(1);
        }

        (void)mktemp(tempfile);                 /* safe */

        lfd = safe_open(LO, O_WRONLY|O_CREAT|O_NOFOLLOW|O_EXLOCK, 0640);
        if (lfd < 0) {
                if (errno == EWOULDBLOCK)       /* active daemon present */
                        exit(0);
                syslog(LOG_ERR, "%s: %s: %m", printer, LO);
                exit(1);
        }
        if (fstat(lfd, &stb) == 0 && (stb.st_mode & S_IXUSR))
                exit(0);                /* printing disabled */
        ftruncate(lfd, 0);
        /*
         * write process id for others to know
         */
        pid = getpid();
        if ((pidoff = i = snprintf(line, sizeof(line), "%d\n", pid)) < 0 ||
            i >= sizeof(line)) {
                syslog(LOG_ERR, "impossibly large pid: %u", pid);
                exit(1);
        }
        if (write(lfd, line, i) != i) {
                syslog(LOG_ERR, "%s: %s: %m", printer, LO);
                exit(1);
        }
        /*
         * search the spool directory for work and sort by queue order.
         */
        if ((nitems = getq(&queue)) < 0) {
                syslog(LOG_ERR, "%s: can't scan %s", printer, SD);
                exit(1);
        }
        if (nitems == 0)                /* no work to do */
                exit(0);
        if (stb.st_mode & S_IXOTH) {            /* reset queue flag */
                stb.st_mode &= ~S_IXOTH;
                if (fchmod(lfd, stb.st_mode & 0777) < 0)
                        syslog(LOG_ERR, "%s: %s: %m", printer, LO);
        }
        PRIV_START;
        openpr();                       /* open printer or remote */
        PRIV_END;

again:
        /*
         * we found something to do now do it --
         *    write the name of the current control file into the lock file
         *    so the spool queue program can tell what we're working on
         */
        for (qp = queue; nitems--; free(q)) {
                q = *qp++;
                if (stat(q->q_name, &stb) < 0)
                        continue;
                errcnt = 0;
        restart:
                fdev = (dev_t)-1;
                fino = (ino_t)-1;

                (void)lseek(lfd, pidoff, SEEK_SET);
                if ((i = snprintf(line, sizeof(line), "%s\n", q->q_name)) < 0 ||
                    i >= sizeof(line))
                        i = sizeof(line) - 1;   /* can't happen */
                if (write(lfd, line, i) != i)
                        syslog(LOG_ERR, "%s: %s: %m", printer, LO);
                if (!remote)
                        i = printit(q->q_name);
                else
                        i = sendit(q->q_name);
                /*
                 * Check to see if we are supposed to stop printing or
                 * if we are to rebuild the queue.
                 */
                if (fstat(lfd, &stb) == 0) {
                        /* stop printing before starting next job? */
                        if (stb.st_mode & S_IXUSR)
                                goto done;
                        /* rebuild queue (after lpc topq) */
                        if (stb.st_mode & S_IXOTH) {
                                for (free(q); nitems--; free(q))
                                        q = *qp++;
                                stb.st_mode &= ~S_IXOTH;
                                if (fchmod(lfd, stb.st_mode & 0777) < 0)
                                        syslog(LOG_WARNING, "%s: %s: %m",
                                                printer, LO);
                                break;
                        }
                }
                if (i == OK)            /* file ok and printed */
                        count++;
                else if (i == REPRINT && ++errcnt < 5) {
                        /* try reprinting the job */
                        syslog(LOG_INFO, "restarting %s", printer);
                        if (ofilter > 0) {
                                kill(ofilter, SIGCONT); /* to be sure */
                                (void)close(ofd);
                                while ((i = wait(NULL)) > 0 && i != ofilter)
                                        ;
                                ofilter = 0;
                        }
                        (void)close(pfd);       /* close printer */
                        if (ftruncate(lfd, pidoff) < 0)
                                syslog(LOG_WARNING, "%s: %s: %m", printer, LO);
                        PRIV_START;
                        openpr();               /* try to reopen printer */
                        PRIV_END;
                        goto restart;
                } else {
                        syslog(LOG_WARNING, "%s: job could not be %s (%s)", printer,
                                remote ? "sent to remote host" : "printed", q->q_name);
                        if (i == REPRINT) {
                                /* ensure we don't attempt this job again */
                                PRIV_START;
                                (void)unlink(q->q_name);
                                q->q_name[0] = 'd';
                                (void)unlink(q->q_name);
                                PRIV_END;
                                if (logname[0])
                                        sendmail(logname, FATALERR);
                        }
                }
        }
        free(queue);
        /*
         * search the spool directory for more work.
         */
        if ((nitems = getq(&queue)) < 0) {
                syslog(LOG_ERR, "%s: can't scan %s", printer, SD);
                exit(1);
        }
        if (nitems == 0) {              /* no more work to do */
        done:
                if (count > 0) {        /* Files actually printed */
                        if (!SF && !tof)
                                (void)write(ofd, FF, strlen(FF));
                        if (TR != NULL)         /* output trailer */
                                (void)write(ofd, TR, strlen(TR));
                }
                (void)close(ofd);
                (void)wait(NULL);
                (void)unlink(tempfile);
                exit(0);
        }
        goto again;
}

#define FONTLEN 50
char    fonts[4][FONTLEN];      /* fonts for troff */

char ifonts[4][40] = {
        _PATH_VFONTR,
        _PATH_VFONTI,
        _PATH_VFONTB,
        _PATH_VFONTS,
};

/*
 * The remaining part is the reading of the control file (cf)
 * and performing the various actions.
 */
static int
printit(char *file)
{
        int i, fd;
        char *cp;
        int bombed = OK;

        /*
         * open control file; ignore if no longer there.
         */
        fd = safe_open(file, O_RDONLY|O_NOFOLLOW, 0);
        if (fd < 0 || (cfp = fdopen(fd, "r")) == NULL) {
                syslog(LOG_INFO, "%s: %s: %m", printer, file);
                if (fd >= 0)
                        (void)close(fd);
                return(OK);
        }
        /*
         * Reset troff fonts.
         */
        for (i = 0; i < 4; i++)
                strlcpy(fonts[i], ifonts[i], FONTLEN);
        (void)snprintf(&width[2], sizeof(width) - 2, "%ld", PW);
        indent[2] = '0';
        indent[3] = '\0';

        /*
         *      read the control file for work to do
         *
         *      file format -- first character in the line is a command
         *      rest of the line is the argument.
         *      valid commands are:
         *
         *              S -- "stat info" for symbolic link protection
         *              J -- "job name" on banner page
         *              C -- "class name" on banner page
         *              L -- "literal" user's name to print on banner
         *              T -- "title" for pr
         *              H -- "host name" of machine where lpr was done
         *              P -- "person" user's login name
         *              I -- "indent" amount to indent output
         *              R -- laser dpi "resolution"
         *              f -- "file name" name of text file to print
         *              l -- "file name" text file with control chars
         *              p -- "file name" text file to print with pr(1)
         *              t -- "file name" troff(1) file to print
         *              n -- "file name" ditroff(1) file to print
         *              d -- "file name" dvi file to print
         *              g -- "file name" plot(1G) file to print
         *              v -- "file name" plain raster file to print
         *              c -- "file name" cifplot file to print
         *              1 -- "R font file" for troff
         *              2 -- "I font file" for troff
         *              3 -- "B font file" for troff
         *              4 -- "S font file" for troff
         *              N -- "name" of file (used by lpq)
         *              U -- "unlink" name of file to remove
         *                    (after we print it. (Pass 2 only)).
         *              M -- "mail" to user when done printing
         *
         *      get_line reads a line and expands tabs to blanks
         */

        /* pass 1 */

        while (get_line(cfp))
                switch (line[0]) {
                case 'H':
                        strlcpy(fromhost, line+1, sizeof(fromhost));
                        if (class[0] == '\0')
                                strlcpy(class, line+1, sizeof(class));
                        continue;

                case 'P':
                        strlcpy(logname, line+1, sizeof(logname));
                        if (RS) {                       /* restricted */
                                if (getpwnam(logname) == NULL) {
                                        bombed = NOACCT;
                                        sendmail(line+1, bombed);
                                        goto pass2;
                                }
                        }
                        continue;

                case 'S':
                        cp = line+1;
                        fdev = 0;
                        while (*cp >= '0' && *cp <= '9')
                                fdev = fdev * 10 + (*cp++ - '0');
                        cp++;
                        fino = 0;
                        while (*cp >= '0' && *cp <= '9')
                                fino = fino * 10 + (*cp++ - '0');
                        continue;

                case 'J':
                        if (line[1] != '\0')
                                strlcpy(jobname, line+1, sizeof(jobname));
                        else {
                                jobname[0] = ' ';
                                jobname[1] = '\0';
                        }
                        continue;

                case 'C':
                        if (line[1] != '\0')
                                strlcpy(class, line+1, sizeof(class));
                        else if (class[0] == '\0')
                                gethostname(class, sizeof(class));
                        continue;

                case 'T':       /* header title for pr */
                        strlcpy(title, line+1, sizeof(title));
                        continue;

                case 'L':       /* identification line */
                        if (!SH && !HL)
                                banner(line+1, jobname);
                        continue;

                case '1':       /* troff fonts */
                case '2':
                case '3':
                case '4':
                        if (line[1] != '\0')
                                strlcpy(fonts[line[0]-'1'], line+1, FONTLEN);
                        continue;

                case 'W':       /* page width */
                        strlcpy(width+2, line+1, sizeof(width) - 2);
                        continue;

                case 'I':       /* indent amount */
                        strlcpy(indent+2, line+1, sizeof(indent) - 2);
                        continue;

                default:        /* some file to print */
                        switch (i = print(line[0], line+1)) {
                        case ERROR:
                                if (bombed == OK)
                                        bombed = FATALERR;
                                break;
                        case REPRINT:
                                (void)fclose(cfp);
                                return(REPRINT);
                        case FILTERERR:
                        case ACCESS:
                                bombed = i;
                                sendmail(logname, bombed);
                        }
                        title[0] = '\0';
                        continue;

                case 'N':
                case 'U':
                case 'M':
                case 'R':
                        continue;
                }

        /* pass 2 */

pass2:
        fseek(cfp, 0L, SEEK_SET);
        while (get_line(cfp))
                switch (line[0]) {
                case 'L':       /* identification line */
                        if (!SH && HL)
                                banner(line+1, jobname);
                        continue;

                case 'M':
                        if (bombed < NOACCT)    /* already sent if >= NOACCT */
                                sendmail(line+1, bombed);
                        continue;

                case 'U':
                        if (strchr(line+1, '/'))
                                continue;
                        (void)unlink(line+1);
                }
        /*
         * clean-up in case another control file exists
         */
        (void)fclose(cfp);
        (void)unlink(file);
        return(bombed == OK ? OK : ERROR);
}

/*
 * Print a file.
 * Set up the chain [ PR [ | {IF, OF} ] ] or {IF, RF, TF, NF, DF, CF, VF}.
 * Return -1 if a non-recoverable error occurred,
 * 2 if the filter detected some errors (but printed the job anyway),
 * 1 if we should try to reprint this job and
 * 0 if all is well.
 * Note: all filters take stdin as the file, stdout as the printer,
 * stderr as the log file, and must not ignore SIGINT.
 */
static int
print(int format, char *file)
{
        ssize_t nread;
        struct stat stb;
        pid_t pid;
        char *prog, *av[17], buf[BUFSIZ];
        int fd, status, serrno;
        int n, fi, fo, p[2], stopped = 0, nofile;

        if (fdev != (dev_t)-1 && fino != (ino_t)-1) {
                /* symbolic link */
                PRIV_START;
                fi = safe_open(file, O_RDONLY, 0);
                PRIV_END;
                if (fi != -1) {
                        /*
                         * The symbolic link should still point to the same file
                         * or someone is trying to print something he shouldn't.
                         */
                        if (fstat(fi, &stb) == -1 ||
                            stb.st_dev != fdev || stb.st_ino != fino) {
                                close(fi);
                                return(ACCESS);
                        }
                }
        } else {
                /* regular file */
                PRIV_START;
                fi = safe_open(file, O_RDONLY|O_NOFOLLOW, 0);
                PRIV_END;
        }
        if (fi == -1)
                return(ERROR);
        if (!SF && !tof) {              /* start on a fresh page */
                (void)write(ofd, FF, strlen(FF));
                tof = 1;
        }
        if (IF == NULL && (format == 'f' || format == 'l' || format == 'o')) {
                tof = 0;
                while ((n = read(fi, buf, BUFSIZ)) > 0)
                        if (write(ofd, buf, n) != n) {
                                (void)close(fi);
                                return(REPRINT);
                        }
                (void)close(fi);
                return(OK);
        }
        switch (format) {
        case 'p':       /* print file using 'pr' */
                if (IF == NULL) {       /* use output filter */
                        prog = _PATH_PR;
                        av[0] = "pr";
                        av[1] = width;
                        av[2] = length;
                        av[3] = "-h";
                        av[4] = *title ? title : " ";
                        av[5] = NULL;
                        fo = ofd;
                        goto start;
                }
                pipe(p);
                if ((prchild = dofork(DORETURN)) == 0) {        /* child */
                        dup2(fi, 0);            /* file is stdin */
                        dup2(p[1], 1);          /* pipe is stdout */
                        closelog();
                        nofile = sysconf(_SC_OPEN_MAX);
                        for (n = 3; n < nofile; n++)
                                (void)close(n);
                        execl(_PATH_PR, "pr", width, length,
                            "-h", *title ? title : " ", (char *)NULL);
                        syslog(LOG_ERR, "cannot execl %s", _PATH_PR);
                        exit(2);
                }
                (void)close(p[1]);              /* close output side */
                (void)close(fi);
                if (prchild < 0) {
                        prchild = 0;
                        (void)close(p[0]);
                        return(ERROR);
                }
                fi = p[0];                      /* use pipe for input */
        case 'f':       /* print plain text file */
                prog = IF;
                av[1] = width;
                av[2] = length;
                av[3] = indent;
                n = 4;
                break;
        case 'o':       /* print postscript file */
                /*
                 * Treat this as a "plain file with control characters", and
                 * assume the standard LPF_INPUT filter will recognize that
                 * the data is postscript and know what to do with it.  These
                 * 'o'-file requests could come from MacOS 10.1 systems.
                 * (later versions of MacOS 10 will explicitly use 'l')
                 * A postscript file can contain binary data, which is why 'l'
                 * is somewhat more appropriate than 'f'.
                 */
                /* FALLTHROUGH */
        case 'l':       /* like 'f' but pass control characters */
                prog = IF;
                av[1] = "-c";
                av[2] = width;
                av[3] = length;
                av[4] = indent;
                n = 5;
                break;
        case 'r':       /* print a fortran text file */
                prog = RF;
                av[1] = width;
                av[2] = length;
                n = 3;
                break;
        case 't':       /* print troff output */
        case 'n':       /* print ditroff output */
        case 'd':       /* print tex output */
                (void)unlink(".railmag");
                if ((fo = open(".railmag", O_CREAT|O_WRONLY|O_EXCL, FILMOD)) < 0) {
                        syslog(LOG_ERR, "%s: cannot create .railmag", printer);
                        (void)unlink(".railmag");
                } else {
                        for (n = 0; n < 4; n++) {
                                if (fonts[n][0] != '/')
                                        (void)write(fo, _PATH_VFONT,
                                            sizeof(_PATH_VFONT) - 1);
                                (void)write(fo, fonts[n], strlen(fonts[n]));
                                (void)write(fo, "\n", 1);
                        }
                        (void)close(fo);
                }
                prog = (format == 't') ? TF : (format == 'n') ? NF : DF;
                av[1] = pxwidth;
                av[2] = pxlength;
                n = 3;
                break;
        case 'c':       /* print cifplot output */
                prog = CF;
                av[1] = pxwidth;
                av[2] = pxlength;
                n = 3;
                break;
        case 'g':       /* print plot(1G) output */
                prog = GF;
                av[1] = pxwidth;
                av[2] = pxlength;
                n = 3;
                break;
        case 'v':       /* print raster output */
                prog = VF;
                av[1] = pxwidth;
                av[2] = pxlength;
                n = 3;
                break;
        default:
                (void)close(fi);
                syslog(LOG_ERR, "%s: illegal format character '%c'",
                        printer, format);
                return(ERROR);
        }
        if (prog == NULL) {
                (void)close(fi);
                syslog(LOG_ERR,
                    "%s: no filter found in printcap for format character '%c'",
                    printer, format);
                return(ERROR);
        }
        if ((av[0] = strrchr(prog, '/')) != NULL)
                av[0]++;
        else
                av[0] = prog;
        av[n++] = "-n";
        av[n++] = logname;
        if (*jobname != '\0' && strcmp(jobname, " ") != 0) {
                av[n++] = "-j";
                av[n++] = jobname;
        }
        av[n++] = "-h";
        av[n++] = fromhost;
        av[n++] = AF;
        av[n] = 0;
        fo = pfd;
        if (ofilter > 0) {              /* stop output filter */
                write(ofd, "\031\1", 2);
                while ((pid = waitpid((pid_t)-1, &status, WUNTRACED)) > 0
                    && pid != ofilter)
                        ;
                if (WIFSTOPPED(status) == 0) {
                        (void)close(fi);
                        syslog(LOG_WARNING,
                            "%s: output filter died (retcode=%d termsig=%d)",
                            printer, WEXITSTATUS(status), WTERMSIG(status));
                        return(REPRINT);
                }
                stopped++;
        }
start:
        if ((child = dofork(DORETURN)) == 0) {  /* child */
                dup2(fi, 0);
                dup2(fo, 1);
                unlink(tempfile);
                n = open(tempfile, O_WRONLY|O_CREAT|O_EXCL, 0664);
                if (n >= 0)
                        dup2(n, 2);
                closelog();
                nofile = sysconf(_SC_OPEN_MAX);
                for (n = 3; n < nofile; n++)
                        (void)close(n);
                execv(prog, av);
                syslog(LOG_ERR, "cannot execv %s", prog);
                _exit(2);
        }
        serrno = errno;
        (void)close(fi);
        errno = serrno;
        if (child < 0) {
                child = prchild = tof = 0;
                syslog(LOG_ERR, "cannot start child process: %m");
                return (ERROR);
        }
        while ((pid = wait(&status)) > 0 && pid != child)
                ;
        child = 0;
        prchild = 0;
        if (stopped) {          /* restart output filter */
                if (kill(ofilter, SIGCONT) < 0) {
                        syslog(LOG_ERR, "cannot restart output filter");
                        exit(1);
                }
        }
        tof = 0;

        /* Copy filter output to "lf" logfile */
        fd = safe_open(tempfile, O_RDONLY|O_NOFOLLOW, 0);
        if (fd >= 0) {
                while ((nread = read(fd, buf, sizeof(buf))) > 0)
                        (void)write(STDERR_FILENO, buf, nread);
                (void)close(fd);
        }

        if (!WIFEXITED(status)) {
                syslog(LOG_WARNING, "%s: filter '%c' terminated (termsig=%d)",
                    printer, format, WTERMSIG(status));
                return(ERROR);
        }
        switch (WEXITSTATUS(status)) {
        case 0:
                tof = 1;
                return(OK);
        case 1:
                return(REPRINT);
        case 2:
                return(ERROR);
        default:
                syslog(LOG_WARNING, "%s: filter '%c' exited (retcode=%d)",
                    printer, format, WEXITSTATUS(status));
                return(FILTERERR);
        }
}

/*
 * Send the daemon control file (cf) and any data files.
 * Return -1 if a non-recoverable error occurred, 1 if a recoverable error and
 * 0 if all is well.
 */
static int
sendit(char *file)
{
        int fd, i, err = OK;
        char *cp, last[BUFSIZ];

        /* open control file */
        fd = safe_open(file, O_RDONLY|O_NOFOLLOW, 0);
        if (fd < 0 || (cfp = fdopen(fd, "r")) == NULL)
                return(OK);
        /*
         *      read the control file for work to do
         *
         *      file format -- first character in the line is a command
         *      rest of the line is the argument.
         *      commands of interest are:
         *
         *            a-z -- "file name" name of file to print
         *              U -- "unlink" name of file to remove
         *                    (after we print it. (Pass 2 only)).
         */

        /*
         * pass 1
         */
        while (get_line(cfp)) {
        again:
                if (line[0] == 'S') {
                        cp = line+1;
                        fdev = 0;
                        while (*cp >= '0' && *cp <= '9')
                                fdev = fdev * 10 + (*cp++ - '0');
                        cp++;
                        fino = 0;
                        while (*cp >= '0' && *cp <= '9')
                                fino = fino * 10 + (*cp++ - '0');
                        continue;
                }
                if (line[0] >= 'a' && line[0] <= 'z') {
                        strlcpy(last, line, sizeof(last));
                        while ((i = get_line(cfp)) != 0)
                                if (strcmp(last, line))
                                        break;
                        switch (sendfile('\3', last+1)) {
                        case OK:
                                if (i)
                                        goto again;
                                break;
                        case REPRINT:
                                (void)fclose(cfp);
                                return(REPRINT);
                        case ACCESS:
                                sendmail(logname, ACCESS);
                        case ERROR:
                                err = ERROR;
                        }
                        break;
                }
        }
        if (err == OK && sendfile('\2', file) > 0) {
                (void)fclose(cfp);
                return(REPRINT);
        }
        /*
         * pass 2
         */
        fseek(cfp, 0L, SEEK_SET);
        while (get_line(cfp))
                if (line[0] == 'U' && strchr(line+1, '/') == 0)
                        (void)unlink(line+1);
        /*
         * clean-up in case another control file exists
         */
        (void)fclose(cfp);
        (void)unlink(file);
        return(err);
}

/*
 * Send a data file to the remote machine and spool it.
 * Return positive if we should try resending.
 */
static int
sendfile(int type, char *file)
{
        int f, i, amt;
        struct stat stb;
        char buf[BUFSIZ];
        int sizerr, resp;

        if (fdev != (dev_t)-1 && fino != (ino_t)-1) {
                /* symbolic link */
                PRIV_START;
                f = safe_open(file, O_RDONLY, 0);
                PRIV_END;
                if (f != -1) {
                        /*
                         * The symbolic link should still point to the same file
                         * or someone is trying to print something he shouldn't.
                         */
                        if (fstat(f, &stb) == -1 ||
                            stb.st_dev != fdev || stb.st_ino != fino) {
                                close(f);
                                return(ACCESS);
                        }
                }
        } else {
                /* regular file */
                PRIV_START;
                f = safe_open(file, O_RDONLY|O_NOFOLLOW, 0);
                PRIV_END;
                if (fstat(f, &stb) == -1) {
                        close(f);
                        f = -1;
                }
        }
        if (f == -1)
                return(ERROR);
        if ((amt = snprintf(buf, sizeof(buf), "%c%lld %s\n", type,
            (long long)stb.st_size, file)) < 0 || amt >= sizeof(buf))
                return (ACCESS);                /* XXX hack */
        for (i = 0;  ; i++) {
                if (write(pfd, buf, amt) != amt ||
                    (resp = response()) < 0 || resp == '\1') {
                        (void)close(f);
                        return(REPRINT);
                } else if (resp == '\0')
                        break;
                if (i == 0)
                        pstatus("no space on remote; waiting for queue to drain");
                if (i == 10)
                        syslog(LOG_ALERT, "%s: can't send to %s; queue full",
                                printer, RM);
                sleep(5 * 60);
        }
        if (i)
                pstatus("sending to %s", RM);
        sizerr = 0;
        for (i = 0; i < stb.st_size; i += BUFSIZ) {
                struct sigaction osa, nsa;

                amt = BUFSIZ;
                if (i + amt > stb.st_size)
                        amt = stb.st_size - i;
                if (sizerr == 0 && read(f, buf, amt) != amt)
                        sizerr = 1;
                memset(&nsa, 0, sizeof(nsa));
                nsa.sa_handler = alarmer;
                sigemptyset(&nsa.sa_mask);
                nsa.sa_flags = 0;
                (void)sigaction(SIGALRM, &nsa, &osa);
                alarm(wait_time);
                if (write(pfd, buf, amt) != amt) {
                        alarm(0);
                        (void)sigaction(SIGALRM, &osa, NULL);
                        (void)close(f);
                        return(REPRINT);
                }
                alarm(0);
                (void)sigaction(SIGALRM, &osa, NULL);
        }

        (void)close(f);
        if (sizerr) {
                syslog(LOG_INFO, "%s: %s: changed size", printer, file);
                /* tell recvjob to ignore this file */
                (void)write(pfd, "\1", 1);
                return(ERROR);
        }
        if (write(pfd, "", 1) != 1 || response())
                return(REPRINT);
        return(OK);
}

/*
 * Check to make sure there have been no errors and that both programs
 * are in sync with eachother.
 * Return non-zero if the connection was lost.
 */
static char
response(void)
{
        struct sigaction osa, nsa;
        char resp;

        memset(&nsa, 0, sizeof(nsa));
        nsa.sa_handler = alarmer;
        sigemptyset(&nsa.sa_mask);
        nsa.sa_flags = 0;
        (void)sigaction(SIGALRM, &nsa, &osa);
        alarm(wait_time);
        if (read(pfd, &resp, 1) != 1) {
                syslog(LOG_INFO, "%s: lost connection", printer);
                resp = -1;
        }
        alarm(0);
        (void)sigaction(SIGALRM, &osa, NULL);
        return (resp);
}

/*
 * Banner printing stuff
 */
static void
banner(char *name1, char *name2)
{
        time_t tvec;

        time(&tvec);
        if (!SF && !tof)
                (void)write(ofd, FF, strlen(FF));
        if (SB) {       /* short banner only */
                if (class[0]) {
                        (void)write(ofd, class, strlen(class));
                        (void)write(ofd, ":", 1);
                }
                (void)write(ofd, name1, strlen(name1));
                (void)write(ofd, "  Job: ", 7);
                (void)write(ofd, name2, strlen(name2));
                (void)write(ofd, "  Date: ", 8);
                (void)write(ofd, ctime(&tvec), 24);
                (void)write(ofd, "\n", 1);
        } else {        /* normal banner */
                (void)write(ofd, "\n\n\n", 3);
                scan_out(ofd, name1, '\0');
                (void)write(ofd, "\n\n", 2);
                scan_out(ofd, name2, '\0');
                if (class[0]) {
                        (void)write(ofd, "\n\n\n", 3);
                        scan_out(ofd, class, '\0');
                }
                (void)write(ofd, "\n\n\n\n\t\t\t\t\tJob:  ", 15);
                (void)write(ofd, name2, strlen(name2));
                (void)write(ofd, "\n\t\t\t\t\tDate: ", 12);
                (void)write(ofd, ctime(&tvec), 24);
                (void)write(ofd, "\n", 1);
        }
        if (!SF)
                (void)write(ofd, FF, strlen(FF));
        tof = 1;
}

static char *
scnline(int key, char *p, int c)
{
        int scnwidth;

        for (scnwidth = WIDTH; --scnwidth;) {
                key <<= 1;
                *p++ = key & 0200 ? c : BACKGND;
        }
        return (p);
}

#define TRC(q)  (((q)-' ')&0177)

static void
scan_out(int scfd, char *scsp, int dlm)
{
        char *strp;
        int nchrs, j;
        char outbuf[LINELEN+1], *sp, c, cc;
        int d, scnhgt;
        extern char scnkey[][HEIGHT];   /* in lpdchar.c */

        for (scnhgt = 0; scnhgt++ < HEIGHT+DROP; ) {
                strp = &outbuf[0];
                sp = scsp;
                for (nchrs = 0; ; ) {
                        d = dropit(c = TRC(cc = *sp++));
                        if ((!d && scnhgt > HEIGHT) || (scnhgt <= DROP && d))
                                for (j = WIDTH; --j;)
                                        *strp++ = BACKGND;
                        else
                                strp = scnline(scnkey[(int)c][scnhgt-1-d],
                                    strp, cc);
                        if (*sp == dlm || *sp == '\0' ||
                            nchrs++ >= PW/(WIDTH+1)-1)
                                break;
                        *strp++ = BACKGND;
                        *strp++ = BACKGND;
                }
                while (*--strp == BACKGND && strp >= outbuf)
                        ;
                strp++;
                *strp++ = '\n'; 
                (void)write(scfd, outbuf, strp-outbuf);
        }
}

static int
dropit(int c)
{
        switch(c) {

        case TRC('_'):
        case TRC(';'):
        case TRC(','):
        case TRC('g'):
        case TRC('j'):
        case TRC('p'):
        case TRC('q'):
        case TRC('y'):
                return (DROP);

        default:
                return (0);
        }
}

/*
 * sendmail ---
 *   tell people about job completion
 */
static void
sendmail(char *user, int bombed)
{
        int i, p[2], s, nofile;
        char *cp = NULL;
        struct stat stb;
        FILE *fp;

        if (user[0] == '-' || user[0] == '/' || !isprint((unsigned char)user[0]))
                return;
        pipe(p);
        if ((s = dofork(DORETURN)) == 0) {              /* child */
                dup2(p[0], 0);
                closelog();
                nofile = sysconf(_SC_OPEN_MAX);
                for (i = 3; i < nofile; i++)
                        (void)close(i);
                if ((cp = strrchr(_PATH_SENDMAIL, '/')) != NULL)
                        cp++;
                else
                        cp = _PATH_SENDMAIL;
                execl(_PATH_SENDMAIL, cp, "-t", (char *)NULL);
                _exit(0);
        } else if (s > 0) {                             /* parent */
                dup2(p[1], 1);
                printf("Auto-Submitted: auto-generated\n");
                printf("To: %s@%s\n", user, fromhost);
                printf("Subject: %s printer job \"%s\"\n", printer,
                        *jobname ? jobname : "<unknown>");
                printf("Reply-To: root@%s\n\n", host);
                printf("Your printer job ");
                if (*jobname)
                        printf("(%s) ", jobname);
                switch (bombed) {
                case OK:
                        printf("\ncompleted successfully\n");
                        cp = "OK";
                        break;
                default:
                case FATALERR:
                        printf("\ncould not be printed\n");
                        cp = "FATALERR";
                        break;
                case NOACCT:
                        printf("\ncould not be printed without an account on %s\n", host);
                        cp = "NOACCT";
                        break;
                case FILTERERR:
                        cp = "FILTERERR";
                        if (stat(tempfile, &stb) < 0 || stb.st_size == 0 ||
                            (fp = fopen(tempfile, "r")) == NULL) {
                                printf("\nhad some errors and may not have printed\n");
                                break;
                        }
                        printf("\nhad the following errors and may not have printed:\n");
                        while ((i = getc(fp)) != EOF)
                                putchar(i);
                        (void)fclose(fp);
                        break;
                case ACCESS:
                        printf("\nwas not printed because it was not linked to the original file\n");
                        cp = "ACCESS";
                }
                fflush(stdout);
                (void)close(1);
        } else {
                syslog(LOG_ERR, "fork for sendmail failed: %m");
        }
        (void)close(p[0]);
        (void)close(p[1]);
        if (s != -1) {
                wait(NULL);
                syslog(LOG_INFO,
                    "mail sent to user %s about job %s on printer %s (%s)",
                    user, *jobname ? jobname : "<unknown>", printer, cp);
        }
}

/* sleep n milliseconds */
static void
delay(int n)
{
        struct timespec tdelay;

        if (n <= 0 || n > 10000)
                fatal("unreasonable delay period (%d)", n);
        tdelay.tv_sec = n / 1000;
        tdelay.tv_nsec = n * 1000000 % 1000000000;
        nanosleep(&tdelay, NULL);
}

/*
 * dofork - fork with retries on failure
 */
static pid_t
dofork(int action)
{
        struct passwd *pw;
        pid_t pid;
        int i;

        for (i = 0; i < 20; i++) {
                if ((pid = fork()) < 0) {
                        sleep((unsigned)(i*i));
                        continue;
                }
                /*
                 * Child should run as daemon instead of root
                 */
                if (pid == 0) {
                        (void)close(lfd);
                        PRIV_START;
                        pw = getpwuid(DU);
                        if (pw == 0) {
                                syslog(LOG_ERR, "uid %ld not in password file",
                                    DU);
                                break;
                        }
                        initgroups(pw->pw_name, pw->pw_gid);
                        setgid(pw->pw_gid);
                        setlogin("");
                        setuid(DU);
                }
                return (pid);
        }
        syslog(LOG_ERR, "can't fork");

        switch (action) {
        case DORETURN:
                return (-1);
        default:
                syslog(LOG_ERR, "bad action (%d) to dofork", action);
                /*FALL THRU*/
        case DOABORT:
                exit(1);
        }
        /*NOTREACHED*/
}

/*
 * Kill child processes to abort current job.
 */
static void
abortpr(int signo)
{
        (void)close(lfd);
        (void)unlink(tempfile);
        (void)kill(0, SIGINT);
        if (ofilter > 0)
                kill(ofilter, SIGCONT);
        while (wait(NULL) > 0)
                ;
        _exit(0);
}

static void
init(void)
{
        int status;
        char *s;

        PRIV_START;
        status = cgetent(&bp, printcapdb, printer);
        PRIV_END;

        switch (status) {
        case -1:
                syslog(LOG_ERR, "unknown printer: %s", printer);
                exit(1);
        case -2:
                syslog(LOG_ERR, "can't open printer description file");
                exit(1);
        case -3:
                fatal("potential reference loop detected in printcap file");
        default:
                break;
        }

        if (cgetstr(bp, DEFLP, &LP) == -1)
                LP = _PATH_DEFDEVLP;
        if (cgetstr(bp, "rp", &RP) == -1)
                RP = DEFLP;
        if (cgetstr(bp, "lo", &LO) == -1)
                LO = DEFLOCK;
        if (cgetstr(bp, "st", &ST) == -1)
                ST = DEFSTAT;
        if (cgetstr(bp, "lf", &LF) == -1)
                LF = _PATH_CONSOLE;
        if (cgetstr(bp, "sd", &SD) == -1)
                SD = _PATH_DEFSPOOL;
        if (cgetnum(bp, "du", &DU) < 0)
                DU = DEFUID;
        if (cgetstr(bp, "ff", &FF) == -1)
                FF = DEFFF;
        if (cgetnum(bp, "pw", &PW) < 0)
                PW = DEFWIDTH;
        (void)snprintf(&width[2], sizeof(width) - 2, "%ld", PW);
        if (cgetnum(bp, "pl", &PL) < 0)
                PL = DEFLENGTH;
        (void)snprintf(&length[2], sizeof(length) - 2, "%ld", PL);
        if (cgetnum(bp, "px", &PX) < 0)
                PX = 0;
        (void)snprintf(&pxwidth[2], sizeof(pxwidth) - 2, "%ld", PX);
        if (cgetnum(bp, "py", &PY) < 0)
                PY = 0;
        (void)snprintf(&pxlength[2], sizeof(pxlength) - 2, "%ld", PY);
        cgetstr(bp, "rm", &RM);
        if ((s = checkremote()) != NULL)
                syslog(LOG_WARNING, "%s", s);

        cgetstr(bp, "af", &AF);
        cgetstr(bp, "of", &OF);
        cgetstr(bp, "if", &IF);
        cgetstr(bp, "rf", &RF);
        cgetstr(bp, "tf", &TF);
        cgetstr(bp, "nf", &NF);
        cgetstr(bp, "df", &DF);
        cgetstr(bp, "gf", &GF);
        cgetstr(bp, "vf", &VF);
        cgetstr(bp, "cf", &CF);
        cgetstr(bp, "tr", &TR);

        RS = (cgetcap(bp, "rs", ':') != NULL);
        SF = (cgetcap(bp, "sf", ':') != NULL);
        SH = (cgetcap(bp, "sh", ':') != NULL);
        SB = (cgetcap(bp, "sb", ':') != NULL);
        HL = (cgetcap(bp, "hl", ':') != NULL);
        RW = (cgetcap(bp, "rw", ':') != NULL);

        cgetnum(bp, "br", &BR);
        cgetstr(bp, "ms", &MS);

        tof = (cgetcap(bp, "fo", ':') == NULL);
}

/*
 * Acquire line printer or remote connection.
 * XXX - should push down privs in here
 */
static void
openpr(void)
{
        int i, nofile;
        char *cp;
        extern int rflag;

        if (!remote && *LP) {
                if ((cp = strchr(LP, '@')))
                        opennet(cp);
                else
                        opentty();
        } else if (remote) {
                openrem();
        } else {
                syslog(LOG_ERR, "%s: no line printer device or host name",
                        printer);
                exit(1);
        }

        /*
         * Start up an output filter, if needed.
         */
        if ((!remote || rflag) && OF) {
                int p[2];

                pipe(p);
                if ((ofilter = dofork(DOABORT)) == 0) { /* child */
                        dup2(p[0], 0);          /* pipe is std in */
                        dup2(pfd, 1);           /* printer is std out */
                        closelog();
                        nofile = sysconf(_SC_OPEN_MAX);
                        for (i = 3; i < nofile; i++)
                                (void)close(i);
                        if ((cp = strrchr(OF, '/')) == NULL)
                                cp = OF;
                        else
                                cp++;
                        execl(OF, cp, width, length, (char *)NULL);
                        syslog(LOG_ERR, "%s: %s: %m", printer, OF);
                        exit(1);
                }
                (void)close(p[0]);              /* close input side */
                ofd = p[1];                     /* use pipe for output */
        } else {
                ofd = pfd;
                ofilter = 0;
        }
}

/*
 * Printer connected directly to the network
 * or to a terminal server on the net
 */
static void
opennet(char *cp)
{
        int i;
        int resp, port;
        char save_ch;

        save_ch = *cp;
        *cp = '\0';
        port = atoi(LP);
        if (port <= 0) {
                syslog(LOG_ERR, "%s: bad port number: %s", printer, LP);
                exit(1);
        }
        *cp++ = save_ch;

        for (i = 1; ; i = i < 256 ? i << 1 : i) {
                resp = -1;
                pfd = getport(cp, port);
                if (pfd < 0 && errno == ECONNREFUSED)
                        resp = 1;
                else if (pfd >= 0) {
                        /*
                         * need to delay a bit for rs232 lines
                         * to stabilize in case printer is
                         * connected via a terminal server
                         */
                        delay(500);
                        break;
                }
                if (i == 1) {
                   if (resp < 0)
                        pstatus("waiting for %s to come up", LP);
                   else
                        pstatus("waiting for access to printer on %s", LP);
                }
                sleep(i);
        }
        pstatus("sending to %s port %d", cp, port);
}

/*
 * Printer is connected to an RS232 port on this host
 */
static void
opentty(void)
{
        int i;

        for (i = 1; ; i = i < 32 ? i << 1 : i) {
                pfd = open(LP, RW ? O_RDWR : O_WRONLY);
                if (pfd >= 0) {
                        delay(500);
                        break;
                }
                if (errno == ENOENT) {
                        syslog(LOG_ERR, "%s: %m", LP);
                        exit(1);
                }
                if (i == 1)
                        pstatus("waiting for %s to become ready (offline ?)",
                                printer);
                sleep(i);
        }
        if (isatty(pfd))
                setty();
        pstatus("%s is ready and printing", printer);
}

/*
 * Printer is on a remote host
 */
static void
openrem(void)
{
        int i, n;
        int resp;

        for (i = 1; ; i = i < 256 ? i << 1 : i) {
                resp = -1;
                pfd = getport(RM, 0);
                if (pfd >= 0) {
                        if ((n = snprintf(line, sizeof(line), "\2%s\n", RP)) < 0 ||
                            n >= sizeof(line))
                                n = sizeof(line) - 1;
                        if (write(pfd, line, n) == n &&
                            (resp = response()) == '\0')
                                break;
                        (void)close(pfd);
                }
                if (i == 1) {
                        if (resp < 0)
                                pstatus("waiting for %s to come up", RM);
                        else {
                                pstatus("waiting for queue to be enabled on %s",
                                        RM);
                                i = 256;
                        }
                }
                sleep(i);
        }
        pstatus("sending to %s", RM);
}

static void
alarmer(int s)
{
        /* nothing */
}

/*
 * setup tty lines.
 */
static void
setty(void)
{
        struct info i;
        char **argv, **ap, **ep, *p, *val;

        i.fd = pfd;
        i.set = i.wset = 0;
        if (ioctl(i.fd, TIOCEXCL, (char *)0) < 0) {
                syslog(LOG_ERR, "%s: ioctl(TIOCEXCL): %m", printer);
                exit(1);
        }
        if (tcgetattr(i.fd, &i.t) < 0) {
                syslog(LOG_ERR, "%s: tcgetattr: %m", printer);
                exit(1);
        }
        if (BR > 0) {
                cfsetspeed(&i.t, BR);
                i.set = 1;
        }
        if (MS) {
                if (ioctl(i.fd, TIOCGETD, &i.ldisc) < 0) {
                        syslog(LOG_ERR, "%s: ioctl(TIOCGETD): %m", printer);
                        exit(1);
                }
                if (ioctl(i.fd, TIOCGWINSZ, &i.win) < 0)
                        syslog(LOG_INFO, "%s: ioctl(TIOCGWINSZ): %m",
                               printer);

                argv = calloc(256, sizeof(char *));
                if (argv == NULL) {
                        syslog(LOG_ERR, "%s: malloc: %m", printer);
                        exit(1);
                }
                p = strdup(MS);
                ap = argv;
                ep = argv + 255;
                while ((val = strsep(&p, " \t,")) != NULL) {
                        if ((*ap++ = strdup(val)) == NULL) {
                                syslog(LOG_ERR, "%s: strdup: %m", printer);
                                exit(1);
                        }
                        if (ap == ep) {
                                syslog(LOG_ERR, "%s: too many \"ms\" entries",
                                    printer);
                                exit(1);
                        }
                }
                *ap = NULL;

                for (; *argv; ++argv) {
                        if (ksearch(&argv, &i))
                                continue;
                        if (msearch(&argv, &i))
                                continue;
                        syslog(LOG_INFO, "%s: unknown stty flag: %s",
                               printer, *argv);
                }
        }

        if (i.set && tcsetattr(i.fd, TCSANOW, &i.t) < 0) {
                syslog(LOG_ERR, "%s: tcsetattr: %m", printer);
                exit(1);
        }
        if (i.wset && ioctl(i.fd, TIOCSWINSZ, &i.win) < 0)
                syslog(LOG_INFO, "%s: ioctl(TIOCSWINSZ): %m", printer);
        return;
}

static void
pstatus(const char *msg, ...)
{
        int fd, len;
        char buf[BUFSIZ];
        va_list ap;

        va_start(ap, msg);
        umask(0);
        fd = open(ST, O_WRONLY|O_CREAT|O_NOFOLLOW|O_EXLOCK, 0660);
        if (fd < 0) {
                syslog(LOG_ERR, "%s: %s: %m", printer, ST);
                exit(1);
        }
        ftruncate(fd, 0);
        len = vsnprintf(buf, sizeof(buf), msg, ap);
        va_end(ap);
        if (len < 0) {
                (void)close(fd);
                return;
        }
        if (len >= sizeof(buf))
                len = sizeof(buf) - 1;
        buf[len++] = '\n';              /* replace NUL with newline */
        (void)write(fd, buf, len);
        (void)close(fd);
}