source: trunk/third/tcsh/sh.c @ 12041

/* $Header: /afs/dev.mit.edu/source/repository/third/tcsh/sh.c,v 1.3 1998-10-04 01:39:28 danw Exp $ */
/*
 * sh.c: Main shell routines
 */
/*-
 * Copyright (c) 1980, 1991 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. 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.
 */
#define EXTERN  /* Intern */
#include "sh.h"

#ifndef lint
char    copyright[] =
"@(#) Copyright (c) 1991 The Regents of the University of California.\n\
 All rights reserved.\n";
#endif /* not lint */

RCSID("$Id: sh.c,v 1.3 1998-10-04 01:39:28 danw Exp $")

#include "tc.h"
#include "ed.h"
#include "tw.h"

extern bool MapsAreInited;
extern bool NLSMapsAreInited;
extern bool NoNLSRebind;

/*
 * C Shell
 *
 * Bill Joy, UC Berkeley, California, USA
 * October 1978, May 1980
 *
 * Jim Kulp, IIASA, Laxenburg, Austria
 * April 1980
 *
 * Filename recognition added:
 * Ken Greer, Ind. Consultant, Palo Alto CA
 * October 1983.
 *
 * Karl Kleinpaste, Computer Consoles, Inc.
 * Added precmd, periodic/tperiod, prompt changes,
 * directory stack hack, and login watch.
 * Sometime March 1983 - Feb 1984.
 *
 * Added scheduled commands, including the "sched" command,
 * plus the call to sched_run near the precmd et al
 * routines.
 * Upgraded scheduled events for running events while
 * sitting idle at command input.
 *
 * Paul Placeway, Ohio State
 * added stuff for running with twenex/inputl  9 Oct 1984.
 *
 * ported to Apple Unix (TM) (OREO)  26 -- 29 Jun 1987
 */

jmp_buf_t reslab INIT_ZERO_STRUCT;

static const char tcshstr[] = "tcsh";
#ifdef WINNT
static const char tcshstr_nt[] = "tcsh.exe";
#endif /* WINNT */

signalfun_t parintr = 0;        /* Parents interrupt catch */
signalfun_t parterm = 0;        /* Parents terminate catch */

#ifdef TESLA
int do_logout = 0;
#endif /* TESLA */


bool    use_fork = 0;           /* use fork() instead of vfork()? */

/*
 * Magic pointer values. Used to specify other invalid conditions aside
 * from null.
 */
static Char     INVCHAR;
Char    *INVPTR = &INVCHAR;
Char    **INVPPTR = &INVPTR;

static int     nofile = 0;
static bool    reenter = 0;
static bool    nverbose = 0;
static bool    nexececho = 0;
static bool    quitit = 0;
static bool    rdirs = 0;
bool    fast = 0;
static bool    batch = 0;
static bool    mflag = 0;
static bool    prompt = 1;
static int     enterhist = 0;
bool    tellwhat = 0;
time_t  t_period;
Char  *ffile = NULL;
bool    dolzero = 0;
int     insource = 0;
static time_t  chktim;          /* Time mail last checked */
char *progname;
int tcsh;
extern char **environ;

/*
 * This preserves the input state of the shell. It is used by
 * st_save and st_restore to manupulate shell state.
 */
struct saved_state {
    int           insource;
    int           SHIN;
    int           intty;
    struct whyle *whyles;
    Char         *gointr;
    Char         *arginp;
    Char         *evalp;
    Char        **evalvec;
    Char         *alvecp;
    Char        **alvec;
    int           onelflg;
    bool          enterhist;
    Char        **argv;
    Char          HIST;
    bool          cantell;
    struct Bin    B;
    /* These keep signal state and setjump state */
#ifdef BSDSIGS
    sigmask_t     mask;
#endif
    jmp_buf_t     oldexit;
    int           reenter;
};

static  int               srccat        __P((Char *, Char *));
static  int               srcfile       __P((char *, bool, int, Char **));
static  sigret_t          phup          __P((int));
static  void              srcunit       __P((int, bool, int, Char **));
static  void              mailchk       __P((void));
#ifndef _PATH_DEFPATH
static  Char            **defaultpath   __P((void));
#endif
static  void              record        __P((void));
static  void              st_save       __P((struct saved_state *, int, int,
                                             Char **, Char **));
static  void              st_restore    __P((struct saved_state *, Char **));

        int               main          __P((int, char **));

int
main(argc, argv)
    int     argc;
    char  **argv;
{
    register Char *cp;
#ifdef AUTOLOGOUT
    register Char *cp2;
#endif
    register char *tcp, *ttyn;
    register int f;
    register char **tempv;

#ifdef BSDSIGS
    sigvec_t osv;
#endif /* BSDSIGS */

#ifdef WINNT
    nt_init();
#endif /* WINNT */
#if defined(NLS_CATALOGS) && defined(LC_MESSAGES)
    (void) setlocale(LC_MESSAGES, "");
#endif /* NLS_CATALOGS && LC_MESSAGES */

#ifdef NLS
# ifdef LC_CTYPE
    (void) setlocale(LC_CTYPE, ""); /* for iscntrl */
# endif /* LC_CTYPE */
#endif /* NLS */

    nlsinit();

#ifdef MALLOC_TRACE
     mal_setstatsfile(fdopen(dup2(open("/tmp/tcsh.trace", 
                                       O_WRONLY|O_CREAT, 0666), 25), "w"));
     mal_trace(1);
#endif /* MALLOC_TRACE */

#if !(defined(BSDTIMES) || defined(_SEQUENT_)) && defined(POSIX)
# ifdef _SC_CLK_TCK
    clk_tck = (clock_t) sysconf(_SC_CLK_TCK);
# else /* ! _SC_CLK_TCK */
#  ifdef CLK_TCK
    clk_tck = CLK_TCK;
#  else /* !CLK_TCK */
    clk_tck = HZ;
#  endif /* CLK_TCK */
# endif /* _SC_CLK_TCK */
#endif /* !BSDTIMES && POSIX */

    settimes();                 /* Immed. estab. timing base */
#ifdef TESLA
    do_logout = 0;
#endif /* TESLA */

    /*
     * Make sure we have 0, 1, 2 open
     * Otherwise `` jobs will not work... (From knaff@poly.polytechnique.fr)
     */
    {
        do 
            if ((f = open(_PATH_DEVNULL, O_RDONLY)) == -1 &&
                (f = open("/", O_RDONLY)) == -1) 
                exit(1);
        while (f < 3);
        (void) close(f);
    }

    osinit();                   /* Os dependent initialization */

    
    {
        char *t;

        t = strrchr(argv[0], '/');
#ifdef WINNT
        {
            char *s = strrchr(argv[0], '\\');
            if (s)
                t = s;
        }
#endif /* WINNT */
        t = t ? t + 1 : argv[0];
        if (*t == '-') t++;
        progname = strsave((t && *t) ? t : tcshstr);    /* never want a null */
        tcsh = strcmp(progname, tcshstr) == 0;
    }

    /*
     * Initialize non constant strings
     */
#ifdef _PATH_BSHELL
    STR_BSHELL = SAVE(_PATH_BSHELL);
#endif
#ifdef _PATH_TCSHELL
    STR_SHELLPATH = SAVE(_PATH_TCSHELL);
#else
# ifdef _PATH_CSHELL
    STR_SHELLPATH = SAVE(_PATH_CSHELL);
# endif
#endif
    STR_environ = blk2short(environ);
    environ = short2blk(STR_environ);   /* So that we can free it */
    STR_WORD_CHARS = SAVE(WORD_CHARS);

    HIST = '!';
    HISTSUB = '^';
    PRCH = '>';
    PRCHROOT = '#';
    word_chars = STR_WORD_CHARS;
    bslash_quote = 0;           /* PWP: do tcsh-style backslash quoting? */

    /* Default history size to 100 */
    set(STRhistory, SAVE("100"), VAR_READWRITE);

    tempv = argv;
    ffile = SAVE(tempv[0]);
    dolzero = 0;
    if (eq(ffile, STRaout))     /* A.out's are quittable */
        quitit = 1;
    uid = getuid();
    gid = getgid();
    euid = geteuid();
    egid = getegid();
#ifdef OREO
    /*
     * We are a login shell if: 1. we were invoked as -<something> with
     * optional arguments 2. or we were invoked only with the -l flag
     */
    loginsh = (**tempv == '-') || (argc == 2 &&
                                   tempv[1][0] == '-' && tempv[1][1] == 'l' &&
                                                tempv[1][2] == '\0');
#else
    /*
     * We are a login shell if: 1. we were invoked as -<something> and we had
     * no arguments 2. or we were invoked only with the -l flag
     */
    loginsh = (**tempv == '-' && argc == 1) || (argc == 2 &&
                                   tempv[1][0] == '-' && tempv[1][1] == 'l' &&
                                                tempv[1][2] == '\0');
#endif

#ifdef _VMS_POSIX
    /* No better way to find if we are a login shell */
    if (!loginsh) {
        loginsh = (argc == 1 && getppid() == 1);
        **tempv = '-';  /* Avoid giving VMS an acidic stomach */
    }
#endif /* _VMS_POSIX */

    if (loginsh && **tempv != '-') {
        /*
         * Mangle the argv space
         */
        tempv[1][0] = '\0';
        tempv[1][1] = '\0';
        tempv[1] = NULL;
        for (tcp = *tempv; *tcp++;)
             continue;
        for (tcp--; tcp >= *tempv; tcp--)
            tcp[1] = tcp[0];
        *++tcp = '-';
        argc--;
    }
    if (loginsh) {
        (void) time(&chktim);
        set(STRloginsh, Strsave(STRNULL), VAR_READWRITE);
    }

    AsciiOnly = 1;
    NoNLSRebind = getenv("NOREBIND") != NULL;
#ifdef NLS
# ifdef SETLOCALEBUG
    dont_free = 1;
# endif /* SETLOCALEBUG */
    (void) setlocale(LC_ALL, "");
# ifdef LC_COLLATE
    (void) setlocale(LC_COLLATE, "");
# endif
# ifdef SETLOCALEBUG
    dont_free = 0;
# endif /* SETLOCALEBUG */
# ifdef STRCOLLBUG
    fix_strcoll_bug();
# endif /* STRCOLLBUG */

    {
        int     k;

        for (k = 0200; k <= 0377 && !Isprint(k); k++)
            continue;
        AsciiOnly = k > 0377;
    }
#else
    AsciiOnly = getenv("LANG") == NULL && getenv("LC_CTYPE") == NULL;
#endif                          /* NLS */
    if (MapsAreInited && !NLSMapsAreInited)
        ed_InitNLSMaps();
    ResetArrowKeys();

    /*
     * Initialize for periodic command intervals. Also, initialize the dummy
     * tty list for login-watch.
     */
    (void) time(&t_period);
#ifndef HAVENOUTMP
    initwatch();
#endif /* !HAVENOUTMP */

#if defined(alliant)
    /*
     * From:  Jim Pace <jdp@research.att.com>
     * tcsh does not work properly on the alliants through an rlogin session.
     * The shell generally hangs.  Also, reference to the controlling terminal
     * does not work ( ie: echo foo > /dev/tty ).
     *
     * A security feature was added to rlogind affecting FX/80's Concentrix
     * from revision 5.5.xx upwards (through 5.7 where this fix was implemented)
     * This security change also affects the FX/2800 series.
     * The security change to rlogind requires the process group of an rlogin
     * session become disassociated with the tty in rlogind.
     *
     * The changes needed are:
     * 1. set the process group
     * 2. reenable the control terminal
     */
     if (loginsh && isatty(SHIN)) {
         ttyn = (char *) ttyname(SHIN);
         (void) close(SHIN);
         SHIN = open(ttyn, O_RDWR);
         shpgrp = getpid();
         (void) ioctl (SHIN, TIOCSPGRP, (ioctl_t) &shpgrp);
         (void) setpgid(0, shpgrp);
     }
#endif /* alliant */

    /*
     * Move the descriptors to safe places. The variable didfds is 0 while we
     * have only FSH* to work with. When didfds is true, we have 0,1,2 and
     * prefer to use these.
     */
    initdesc();

    /*
     * Get and set the tty now
     */
    if ((ttyn = ttyname(SHIN)) != NULL) {
        /*
         * Could use rindex to get rid of other possible path components, but
         * hpux preserves the subdirectory /pty/ when storing the tty name in
         * utmp, so we keep it too.
         */
        if (strncmp(ttyn, "/dev/", 5) == 0)
            set(STRtty, cp = SAVE(ttyn + 5), VAR_READWRITE);
        else
            set(STRtty, cp = SAVE(ttyn), VAR_READWRITE);
    }
    else
        set(STRtty, cp = SAVE(""), VAR_READWRITE);
    /*
     * Initialize the shell variables. ARGV and PROMPT are initialized later.
     * STATUS is also munged in several places. CHILD is munged when
     * forking/waiting
     */

    /*
     * 7-10-87 Paul Placeway autologout should be set ONLY on login shells and
     * on shells running as root.  Out of these, autologout should NOT be set
     * for any psudo-terminals (this catches most window systems) and not for
     * any terminal running X windows.
     * 
     * At Ohio State, we have had problems with a user having his X session 
     * drop out from under him (on a Sun) because the shell in his master 
     * xterm timed out and exited.
     * 
     * Really, this should be done with a program external to the shell, that
     * watches for no activity (and NO running programs, such as dump) on a
     * terminal for a long peroid of time, and then SIGHUPS the shell on that
     * terminal.
     * 
     * bugfix by Rich Salz <rsalz@PINEAPPLE.BBN.COM>: For root rsh things 
     * allways first check to see if loginsh or really root, then do things 
     * with ttyname()
     * 
     * Also by Jean-Francois Lamy <lamy%ai.toronto.edu@RELAY.CS.NET>: check the
     * value of cp before using it! ("root can rsh too")
     * 
     * PWP: keep the nested ifs; the order of the tests matters and a good 
     * (smart) C compiler might re-arange things wrong.
     */
#ifdef AUTOLOGOUT
# ifdef convex
    if (uid == 0) {
        /*  root always has a 15 minute autologout  */
        set(STRautologout, Strsave(STRrootdefautologout));
    }
    else
        if (loginsh)
            /*  users get autologout set to 0  */
            set(STRautologout, Strsave(STR0));
# else /* convex */
    if (loginsh || (uid == 0)) {
        if (*cp) {
            /* only for login shells or root and we must have a tty */
            if ((cp2 = Strrchr(cp, (Char) '/')) != NULL) {
                cp = cp2 + 1;
            }
            else
                cp2 = cp;
            if (!(((Strncmp(cp2, STRtty, 3) == 0) && Isalpha(cp2[3])) ||
                  ((Strncmp(cp, STRpts, 3) == 0) && cp[3] == '/'))) {
                if (getenv("DISPLAY") == NULL) {
                    /* NOT on X window shells */
                    set(STRautologout, Strsave(STRdefautologout), 
                        VAR_READWRITE);
                }
            }
        }
    }
# endif /* convex */
#endif /* AUTOLOGOUT */

    (void) sigset(SIGALRM, alrmcatch);

    set(STRstatus, Strsave(STR0), VAR_READWRITE);

    /*
     * get and set machine specific envirnment variables
     */
    getmachine();

    fix_version();              /* publish the shell version */

    /*
     * Publish the selected echo style
     */
#if ECHO_STYLE == NONE_ECHO
    set(STRecho_style, Strsave(STRnone), VAR_READWRITE);
#endif /* ECHO_STYLE == NONE_ECHO */
#if ECHO_STYLE == BSD_ECHO
    set(STRecho_style, Strsave(STRbsd), VAR_READWRITE);
#endif /* ECHO_STYLE == BSD_ECHO */
#if ECHO_STYLE == SYSV_ECHO
    set(STRecho_style, Strsave(STRsysv), VAR_READWRITE);
#endif /* ECHO_STYLE == SYSV_ECHO */
#if ECHO_STYLE == BOTH_ECHO
    set(STRecho_style, Strsave(STRboth), VAR_READWRITE);
#endif /* ECHO_STYLE == BOTH_ECHO */

    /*
     * increment the shell level.
     */
    shlvl(1);

    if ((tcp = getenv("HOME")) != NULL)
        cp = quote(SAVE(tcp));
    else
        cp = NULL;
    if (cp == NULL)
        fast = 1;               /* No home -> can't read scripts */
    else
        set(STRhome, cp, VAR_READWRITE);
    dinit(cp);                  /* dinit thinks that HOME == cwd in a login
                                 * shell */
    /*
     * Grab other useful things from the environment. Should we grab
     * everything??
     */
    {
        char *cln, *cus, *cgr;
        Char    buff[BUFSIZE];
        struct passwd *pw;
        struct group *gr;


#ifdef apollo
        int     oid = getoid();

        Itoa(oid, buff);
        set(STRoid, Strsave(buff), VAR_READWRITE);
#endif /* apollo */

        Itoa(uid, buff);
        set(STRuid, Strsave(buff), VAR_READWRITE);

        Itoa(gid, buff);
        set(STRgid, Strsave(buff), VAR_READWRITE);

        cln = getenv("LOGNAME");
        cus = getenv("USER");
        if (cus != NULL)
            set(STRuser, quote(SAVE(cus)), VAR_READWRITE);
        else if (cln != NULL)
            set(STRuser, quote(SAVE(cln)), VAR_READWRITE);
        else if ((pw = getpwuid(uid)) == NULL)
            set(STRuser, SAVE("unknown"), VAR_READWRITE);
        else
            set(STRuser, SAVE(pw->pw_name), VAR_READWRITE);
        if (cln == NULL)
            tsetenv(STRLOGNAME, varval(STRuser));
        if (cus == NULL)
            tsetenv(STRKUSER, varval(STRuser));
        
        cgr = getenv("GROUP");
        if (cgr != NULL)
            set(STRgroup, quote(SAVE(cgr)), VAR_READWRITE);
        else if ((gr = getgrgid(gid)) == NULL)
            set(STRgroup, SAVE("unknown"), VAR_READWRITE);
        else
            set(STRgroup, SAVE(gr->gr_name), VAR_READWRITE);
        if (cgr == NULL)
            tsetenv(STRKGROUP, varval(STRgroup));
    }

    /*
     * HOST may be wrong, since rexd transports the entire environment on sun
     * 3.x Just set it again
     */
    {
        char    cbuff[MAXHOSTNAMELEN];

        if (gethostname(cbuff, sizeof(cbuff)) >= 0) {
            cbuff[sizeof(cbuff) - 1] = '\0';    /* just in case */
            tsetenv(STRHOST, str2short(cbuff));
        }
        else
            tsetenv(STRHOST, str2short("unknown"));
    }


#ifdef REMOTEHOST
    /*
     * Try to determine the remote host we were logged in from.
     */
    remotehost();
#endif /* REMOTEHOST */
 
#ifdef apollo
    if ((tcp = getenv("SYSTYPE")) == NULL)
        tcp = "bsd4.3";
    tsetenv(STRSYSTYPE, quote(str2short(tcp)));
#endif /* apollo */

    /*
     * set editing on by default, unless running under Emacs as an inferior
     * shell.
     * We try to do this intelligently. If $TERM is available, then it
     * should determine if we should edit or not. $TERM is preserved
     * across rlogin sessions, so we will not get confused if we rlogin
     * under an emacs shell. Another advantage is that if we run an
     * xterm under an emacs shell, then the $TERM will be set to 
     * xterm, so we are going to want to edit. Unfortunately emacs
     * does not restore all the tty modes, so xterm is not very well
     * set up. But this is not the shell's fault.
     * Also don't edit if $TERM == wm, for when we're running under an ATK app.
     * Finally, emacs compiled under terminfo, sets the terminal to dumb,
     * so disable editing for that too.
     * 
     * Unfortunately, in some cases the initial $TERM setting is "unknown",
     * "dumb", or "network" which is then changed in the user's startup files.
     * We fix this by setting noediting here if $TERM is unknown/dumb and
     * if noediting is set, we switch on editing if $TERM is changed.
     */
    if ((tcp = getenv("TERM")) != NULL) {
        set(STRterm, quote(SAVE(tcp)), VAR_READWRITE);
        noediting = strcmp(tcp, "unknown") == 0 || strcmp(tcp, "dumb") == 0 ||
                    strcmp(tcp, "network") == 0;
        editing = strcmp(tcp, "emacs") != 0 && strcmp(tcp, "wm") != 0 &&
                  !noediting;
    }
    else {
        noediting = 0;
        editing = ((tcp = getenv("EMACS")) == NULL || strcmp(tcp, "t") != 0);
    }

    /* 
     * The 'edit' variable is either set or unset.  It doesn't 
     * need a value.  Making it 'emacs' might be confusing. 
     */
    if (editing)
        set(STRedit, Strsave(STRNULL), VAR_READWRITE);


    /*
     * still more mutability: make the complete routine automatically add the
     * suffix of file names...
     */
    set(STRaddsuffix, Strsave(STRNULL), VAR_READWRITE);

    /*
     * Re-initialize path if set in environment
     */
    if ((tcp = getenv("PATH")) == NULL)
#ifdef _PATH_DEFPATH
        importpath(str2short(_PATH_DEFPATH));
#else /* !_PATH_DEFPATH */
        setq(STRpath, defaultpath(), &shvhed, VAR_READWRITE);
#endif /* _PATH_DEFPATH */
    else
        /* Importpath() allocates memory for the path, and the
         * returned pointer from SAVE() was discarded, so
         * this was a memory leak.. (sg)
         *
         * importpath(SAVE(tcp));
         */
        importpath(str2short(tcp));


    {
        /* If the SHELL environment variable ends with "tcsh", set
         * STRshell to the same path.  This is to facilitate using
         * the executable in environments where the compiled-in
         * default isn't appropriate (sg).
         */

        int sh_len = 0;

        if ((tcp = getenv("SHELL")) != NULL) {
            sh_len = strlen(tcp);
            if ((sh_len >= 5 && strcmp(tcp + (sh_len - 5), "/tcsh") == 0) || 
                (sh_len >= 4 && strcmp(tcp + (sh_len - 4), "/csh") == 0))
                set(STRshell, quote(SAVE(tcp)), VAR_READWRITE);
            else
                sh_len = 0;
        }
        if (sh_len == 0)
            set(STRshell, Strsave(STR_SHELLPATH), VAR_READWRITE);
    }

#ifdef COLOR_LS_F
    if ((tcp = getenv("LS_COLORS")) != NULL)
        parseLS_COLORS(str2short(tcp));
#endif /* COLOR_LS_F */

    doldol = putn((int) getpid());      /* For $$ */
#ifdef WINNT
    {
        char *strtmp1, strtmp2[MAXPATHLEN];
        if ((strtmp1 = getenv("TMP")) != NULL)
            wsprintf(strtmp2, "%s/%s", strtmp1, "sh");
        shtemp = Strspl(SAVE(strtmp2), doldol); /* For << */
    }
#else /* !WINNT */
    shtemp = Strspl(STRtmpsh, doldol);  /* For << */
#endif /* WINNT */

    /*
     * Record the interrupt states from the parent process. If the parent is
     * non-interruptible our hand must be forced or we (and our children) won't
     * be either. Our children inherit termination from our parent. We catch it
     * only if we are the login shell.
     */
#ifdef BSDSIGS
    /* 
     * PURIFY-2 claims that osv does not get 
     * initialized after the sigvec call
     */
    setzero((char*) &osv, sizeof(osv));
    /* parents interruptibility */
    (void) mysigvec(SIGINT, NULL, &osv);
    parintr = (signalfun_t) osv.sv_handler;
    (void) mysigvec(SIGTERM, NULL, &osv);
    parterm = (signalfun_t) osv.sv_handler;
#else                           /* BSDSIGS */
    parintr = signal(SIGINT, SIG_IGN);  /* parents interruptibility */
    (void) sigset(SIGINT, parintr);     /* ... restore */

# ifdef COHERENT
    if (loginsh) /* it seems that SIGTERM is always set to SIG_IGN by */
                 /* init/getty so it should be set to SIG_DFL - there may be */
                 /* a better fix for this. */
         parterm = SIG_DFL;
    else
# else /* !COHERENT */
    parterm = signal(SIGTERM, SIG_IGN); /* parents terminability */
# endif /* COHERENT */
    (void) sigset(SIGTERM, parterm);    /* ... restore */

#endif /* BSDSIGS */


#ifdef TCF
    /* Enable process migration on ourselves and our progeny */
    (void) signal(SIGMIGRATE, SIG_DFL);
#endif /* TCF */

    /*
     * Process the arguments.
     * 
     * Note that processing of -v/-x is actually delayed till after script
     * processing.
     * 
     * We set the first character of our name to be '-' if we are a shell 
     * running interruptible commands.  Many programs which examine ps'es 
     * use this to filter such shells out.
     */
    argc--, tempv++;
    while (argc > 0 && (tcp = tempv[0])[0] == '-' &&
           *++tcp != '\0' && !batch) {
        do
            switch (*tcp++) {

            case 0:             /* -    Interruptible, no prompt */
                prompt = 0;
                setintr = 1;
                nofile = 1;
                break;

            case 'b':           /* -b   Next arg is input file */
                batch = 1;
                break;

            case 'c':           /* -c   Command input from arg */
                if (argc == 1)
                    xexit(0);
                argc--, tempv++;
#ifdef M_XENIX
                /* Xenix Vi bug:
                   it relies on a 7 bit environment (/bin/sh), so it
                   pass ascii arguments with the 8th bit set */
                if (!strcmp(argv[0], "sh"))
                  {
                    char *p;

                    for (p = tempv[0]; *p; ++p)
                      *p &= ASCII;
                  }
#endif
                arginp = SAVE(tempv[0]);

                /*
                 * we put the command into a variable
                 */
                if (arginp != NULL)
                  set(STRcommand, quote(Strsave(arginp)), VAR_READWRITE);

                /*
                 * * Give an error on -c arguments that end in * backslash to
                 * ensure that you don't make * nonportable csh scripts.
                 */
                {
                    register int count;

                    cp = arginp + Strlen(arginp);
                    count = 0;
                    while (cp > arginp && *--cp == '\\')
                        ++count;
                    if ((count & 1) != 0) {
                        exiterr = 1;
                        stderror(ERR_ARGC);
                    }
                }
                prompt = 0;
                nofile = 1;
                break;
            case 'd':           /* -d   Load directory stack from file */
                rdirs = 1;
                break;

#ifdef apollo
            case 'D':           /* -D   Define environment variable */
                {
                    register Char *dp;

                    cp = str2short(tcp);
                    if (dp = Strchr(cp, '=')) {
                        *dp++ = '\0';
                        tsetenv(cp, dp);
                    }
                    else
                        tsetenv(cp, STRNULL);
                }
                *tcp = '\0';    /* done with this argument */
                break;
#endif /* apollo */

            case 'e':           /* -e   Exit on any error */
                exiterr = 1;
                break;

            case 'f':           /* -f   Fast start */
                fast = 1;
                break;

            case 'i':           /* -i   Interactive, even if !intty */
                intact = 1;
                nofile = 1;
                break;

            case 'm':           /* -m   read .cshrc (from su) */
                mflag = 1;
                break;

            case 'n':           /* -n   Don't execute */
                noexec = 1;
                break;

            case 'q':           /* -q   (Undoc'd) ... die on quit */
                quitit = 1;
                break;

            case 's':           /* -s   Read from std input */
                nofile = 1;
                break;

            case 't':           /* -t   Read one line from input */
                onelflg = 2;
                prompt = 0;
                nofile = 1;
                break;

            case 'v':           /* -v   Echo hist expanded input */
                nverbose = 1;   /* ... later */
                break;

            case 'x':           /* -x   Echo just before execution */
                nexececho = 1;  /* ... later */
                break;

            case 'V':           /* -V   Echo hist expanded input */
                setNS(STRverbose);      /* NOW! */
                break;

            case 'X':           /* -X   Echo just before execution */
                setNS(STRecho); /* NOW! */
                break;

            case 'F':           /* Undocumented flag */
                /*
                 * This will cause children to be created using fork instead of
                 * vfork.
                 */
                use_fork = 1;
                break;

            case ' ':
            case '\t':
                /* 
                 * for O/S's that don't do the argument parsing right in 
                 * "#!/foo -f " scripts
                 */
                break;

            default:            /* Unknown command option */
                exiterr = 1;
                stderror(ERR_TCSHUSAGE, tcp-1, progname);
                break;

        } while (*tcp);
        tempv++, argc--;
    }

    if (quitit)                 /* With all due haste, for debugging */
        (void) signal(SIGQUIT, SIG_DFL);

    /*
     * Unless prevented by -, -c, -i, -s, or -t, if there are remaining
     * arguments the first of them is the name of a shell file from which to
     * read commands.
     */
    if (nofile == 0 && argc > 0) {
        nofile = open(tempv[0], O_RDONLY);
        if (nofile < 0) {
            child = 1;          /* So this ... */
            /* ... doesn't return */
            stderror(ERR_SYSTEM, tempv[0], strerror(errno));
        }
        if (ffile != NULL)
            xfree((ptr_t) ffile);
        dolzero = 1;
        ffile = SAVE(tempv[0]);
        /* 
         * Replace FSHIN. Handle /dev/std{in,out,err} specially
         * since once they are closed we cannot open them again.
         * In that case we use our own saved descriptors
         */
        if ((SHIN = dmove(nofile, FSHIN)) < 0) 
            switch(nofile) {
            case 0:
                SHIN = FSHIN;
                break;
            case 1:
                SHIN = FSHOUT;
                break;
            case 2:
                SHIN = FSHDIAG;
                break;
            default:
                stderror(ERR_SYSTEM, tempv[0], strerror(errno));
                break;
            }
        (void) close_on_exec(SHIN, 1);
        prompt = 0;
         /* argc not used any more */ tempv++;
    }


    /*
     * Consider input a tty if it really is or we are interactive. but not for
     * editing (christos)
     */
    if (!(intty = isatty(SHIN))) {
        if (adrof(STRedit))
            unsetv(STRedit);
        editing = 0;
    }
    intty |= intact;
#ifndef convex
    if (intty || (intact && isatty(SHOUT))) {
        if (!batch && (uid != euid || gid != egid)) {
            errno = EACCES;
            child = 1;          /* So this ... */
            /* ... doesn't return */
            stderror(ERR_SYSTEM, progname, strerror(errno));
        }
    }
#endif /* convex */
    isoutatty = isatty(SHOUT);
    isdiagatty = isatty(SHDIAG);
    /*
     * Decide whether we should play with signals or not. If we are explicitly
     * told (via -i, or -) or we are a login shell (arg0 starts with -) or the
     * input and output are both the ttys("csh", or "csh</dev/ttyx>/dev/ttyx")
     * Note that in only the login shell is it likely that parent may have set
     * signals to be ignored
     */
    if (loginsh || intact || (intty && isatty(SHOUT)))
        setintr = 1;
    settell();
    /*
     * Save the remaining arguments in argv.
     */
    setq(STRargv, blk2short(tempv), &shvhed, VAR_READWRITE);

    /*
     * Set up the prompt.
     */
    if (prompt) {
        if (tcsh)
            set(STRprompt, Strsave(STRdeftcshprompt), VAR_READWRITE);
        else
            set(STRprompt, Strsave(STRdefcshprompt), VAR_READWRITE);
        /* that's a meta-questionmark */
        set(STRprompt2, Strsave(STRmquestion), VAR_READWRITE);
        set(STRprompt3, Strsave(STRKCORRECT), VAR_READWRITE);
    }

    /*
     * If we are an interactive shell, then start fiddling with the signals;
     * this is a tricky game.
     */
    shpgrp = mygetpgrp();
    opgrp = tpgrp = -1;
    if (setintr) {
        signalfun_t osig;
        **argv = '-';
        if (!quitit)            /* Wary! */
            (void) signal(SIGQUIT, SIG_IGN);
        (void) sigset(SIGINT, pintr);
        (void) sighold(SIGINT);
        (void) signal(SIGTERM, SIG_IGN);

        /* 
         * No reason I can see not to save history on all these events..
         * Most usual occurrence is in a window system, where we're not a login
         * shell, but might as well be... (sg)
         * But there might be races when lots of shells exit together...
         * [this is also incompatible].
         * We have to be mre careful here. If the parent wants to 
         * ignore the signals then we leave them untouched...
         * We also only setup the handlers for shells that are trully
         * interactive.
         */
        osig = signal(SIGHUP, phup);    /* exit processing on HUP */
        if (!loginsh && osig == SIG_IGN)
            (void) signal(SIGHUP, osig);
#ifdef SIGXCPU
        osig = signal(SIGXCPU, phup);   /* exit processing on XCPU */
        if (!loginsh && osig == SIG_IGN)
            (void) signal(SIGXCPU, osig);
#endif
#ifdef SIGXFSZ
        osig = signal(SIGXFSZ, phup);   /* exit processing on XFSZ */
        if (!loginsh && osig == SIG_IGN)
            (void) signal(SIGXFSZ, osig);
#endif

        if (quitit == 0 && arginp == 0) {
#ifdef SIGTSTP
            (void) signal(SIGTSTP, SIG_IGN);
#endif
#ifdef SIGTTIN
            (void) signal(SIGTTIN, SIG_IGN);
#endif
#ifdef SIGTTOU
            (void) signal(SIGTTOU, SIG_IGN);
#endif
            /*
             * Wait till in foreground, in case someone stupidly runs csh &
             * dont want to try to grab away the tty.
             */
            if (isatty(FSHDIAG))
                f = FSHDIAG;
            else if (isatty(FSHOUT))
                f = FSHOUT;
            else if (isatty(OLDSTD))
                f = OLDSTD;
            else
                f = -1;

#ifdef NeXT
            /* NeXT 2.0 /usr/etc/rlogind, does not set our process group! */
            if (shpgrp == 0) {
                shpgrp = getpid();
                (void) setpgid(0, shpgrp);
                (void) tcsetpgrp(f, shpgrp);
            }
#endif /* NeXT */
#ifdef BSDJOBS                  /* if we have tty job control */
    retry:
            if ((tpgrp = tcgetpgrp(f)) != -1) {
                if (tpgrp != shpgrp) {
                    signalfun_t old = signal(SIGTTIN, SIG_DFL);
                    (void) kill(0, SIGTTIN);
                    (void) signal(SIGTTIN, old);
                    goto retry;
                }
                /*
                 * Thanks to Matt Day for the POSIX references, and to
                 * Paul Close for the SGI clarification.
                 */
                if (setdisc(f) != -1) {
                    opgrp = shpgrp;
                    shpgrp = getpid();
                    tpgrp = shpgrp;
                    if (tcsetpgrp(f, shpgrp) == -1) {
                        /*
                         * On hpux 7.03 this fails with EPERM. This happens on
                         * the 800 when opgrp != shpgrp at this point. (we were
                         * forked from a non job control shell)
                         * POSIX 7.2.4, says we failed because the process
                         * group specified did not belong to a process
                         * in the same session with the tty. So we set our
                         * process group and try again.
                         */
                        if (setpgid(0, shpgrp) == -1) {
                            xprintf("setpgid:");
                            goto notty;
                        }
                        if (tcsetpgrp(f, shpgrp) == -1) {
                            xprintf("tcsetpgrp:");
                            goto notty;
                        }
                    }
                    /*
                     * We check the process group now. If it is the same, then
                     * we don't need to set it again. On hpux 7.0 on the 300's
                     * if we set it again it fails with EPERM. This is the
                     * correct behavior according to POSIX 4.3.3 if the process
                     * was a session leader .
                     */
                    else if (shpgrp != mygetpgrp()) {
                        if(setpgid(0, shpgrp) == -1) {
                            xprintf("setpgid:");
                            goto notty;
                        }
                    }
#ifdef IRIS4D
                    /*
                     * But on irix 3.3 we need to set it again, even if it is
                     * the same. We do that to tell the system that we
                     * need BSD process group compatibility.
                     */
                    else
                        (void) setpgid(0, shpgrp);
#endif
                    (void) close_on_exec(dcopy(f, FSHTTY), 1);
                }
                else
                    tpgrp = -1;
            }
            if (tpgrp == -1) {
        notty:
                xprintf(CGETS(11, 1, "Warning: no access to tty (%s).\n"),
                        strerror(errno));
                xprintf(CGETS(11, 2, "Thus no job control in this shell.\n"));
                /*
                 * Fix from:Sakari Jalovaara <sja@sirius.hut.fi> if we don't
                 * have access to tty, disable editing too
                 */
                if (adrof(STRedit))
                    unsetv(STRedit);
                editing = 0;
            }
#else   /* BSDJOBS */           /* don't have job control, so frotz it */
            tpgrp = -1;
#endif                          /* BSDJOBS */
        }
    }
    if ((setintr == 0) && (parintr == SIG_DFL))
        setintr = 1;

/*
 * SVR4 doesn't send a SIGCHLD when a child is stopped or continued if the
 * handler is installed with signal(2) or sigset(2).  sigaction(2) must
 * be used instead.
 *
 * David Dawes (dawes@physics.su.oz.au) Sept 1991
 */

#if SYSVREL > 3
    {
        struct sigaction act;
        act.sa_handler=pchild;
        (void) sigemptyset(&(act.sa_mask));     /* Don't block any extra sigs
                                                 * when the handler is called
                                                 */
        act.sa_flags=0;            /* want behaviour of sigset() without
                                    * SA_NOCLDSTOP
                                    */

        if ((sigaction(SIGCHLD,&act,(struct sigaction *)NULL)) == -1)
            stderror(ERR_SYSTEM, "sigaction", strerror(errno));
    }
#else /* SYSVREL <= 3 */
    (void) sigset(SIGCHLD, pchild);     /* while signals not ready */
#endif /* SYSVREL <= 3 */


    if (intty && !arginp)       
        (void) ed_Setup(editing);/* Get the tty state, and set defaults */
                                 /* Only alter the tty state if editing */
    
    /*
     * Set an exit here in case of an interrupt or error reading the shell
     * start-up scripts.
     */
    reenter = setexit();        /* PWP */
    haderr = 0;                 /* In case second time through */
    if (!fast && reenter == 0) {
        /* Will have varval(STRhome) here because set fast if don't */
        {
            int     osetintr = setintr;
            signalfun_t oparintr = parintr;

#ifdef BSDSIGS
            sigmask_t omask = sigblock(sigmask(SIGINT));
#else
            (void) sighold(SIGINT);
#endif
            setintr = 0;
            parintr = SIG_IGN;  /* onintr in /etc/ files has no effect */
#ifdef LOGINFIRST
#ifdef _PATH_DOTLOGIN
            if (loginsh)
              (void) srcfile(_PATH_DOTLOGIN, 0, 0, NULL);
#endif
#endif

#ifdef _PATH_DOTCSHRC
            (void) srcfile(_PATH_DOTCSHRC, 0, 0, NULL);
#endif
            if (!arginp && !onelflg && !havhash)
                dohash(NULL,NULL);
#ifndef LOGINFIRST
#ifdef _PATH_DOTLOGIN
            if (loginsh)
                (void) srcfile(_PATH_DOTLOGIN, 0, 0, NULL);
#endif
#endif
#ifdef BSDSIGS
            (void) sigsetmask(omask);
#else
            (void) sigrelse(SIGINT);
#endif
            setintr = osetintr;
            parintr = oparintr;
        }
#ifdef LOGINFIRST
        if (loginsh)
            (void) srccat(varval(STRhome), STRsldotlogin);
#endif
        (void) srccat(varval(STRhome), STRsldottcshrc);
        (void) srccat(varval(STRhome), STRsldotcshrc);

        if (!fast && !arginp && !onelflg && !havhash)
            dohash(NULL,NULL);

        /*
         * Source history before .login so that it is available in .login
         */
        loadhist(NULL, 0);
#ifndef LOGINFIRST
        if (loginsh)
            (void) srccat(varval(STRhome), STRsldotlogin);
#endif
        if (!fast && (loginsh || rdirs))
            loaddirs(NULL);
    }
    /* Initing AFTER .cshrc is the Right Way */
    if (intty && !arginp) {     /* PWP setup stuff */
        ed_Init();              /* init the new line editor */
#ifdef SIG_WINDOW
        check_window_size(1);   /* mung environment */
#endif                          /* SIG_WINDOW */
    }

    /*
     * dspkanji/dspmbyte autosetting
     */
    /* PATCH IDEA FROM Issei.Suzuki VERY THANKS */
#if defined(DSPMBYTE)
    if ((tcp = getenv("LANG")) != NULL && !adrof(CHECK_MBYTEVAR)) {
        autoset_dspmbyte(str2short(tcp));
    }
#if defined(WINNT)
    else if (!adrof(CHECK_MBYTEVAR))
      nt_autoset_dspmbyte();
#endif /* WINNT */
#endif

    /*
     * Now are ready for the -v and -x flags
     */
    if (nverbose)
        setNS(STRverbose);
    if (nexececho)
        setNS(STRecho);
    
    /*
     * All the rest of the world is inside this call. The argument to process
     * indicates whether it should catch "error unwinds".  Thus if we are a
     * interactive shell our call here will never return by being blown past on
     * an error.
     */
    process(setintr);

    /*
     * Mop-up.
     */
    if (intty) {
        if (loginsh) {
            xprintf("logout\n");
            (void) close(SHIN);
            child = 1;
#ifdef TESLA
            do_logout = 1;
#endif                          /* TESLA */
            goodbye(NULL, NULL);
        }
        else {
            xprintf("exit\n");
        }
    }
    record();
    exitstat();
    return (0);
}

void
untty()
{
#ifdef BSDJOBS
    if (tpgrp > 0 && opgrp != shpgrp) {
        (void) setpgid(0, opgrp);
        (void) tcsetpgrp(FSHTTY, opgrp);
        (void) resetdisc(FSHTTY);
    }
#endif /* BSDJOBS */
}

void
importpath(cp)
    Char   *cp;
{
    register int i = 0;
    register Char *dp;
    register Char **pv;
    int     c;

    for (dp = cp; *dp; dp++)
        if (*dp == PATHSEP)
            i++;
    /*
     * i+2 where i is the number of colons in the path. There are i+1
     * directories in the path plus we need room for a zero terminator.
     */
    pv = (Char **) xcalloc((size_t) (i + 2), sizeof(Char *));
    dp = cp;
    i = 0;
    if (*dp)
        for (;;) {
            if ((c = *dp) == PATHSEP || c == 0) {
                *dp = 0;
                pv[i++] = Strsave(*cp ? cp : STRdot);
                if (c) {
                    cp = dp + 1;
                    *dp = PATHSEP;
                }
                else
                    break;
            }
#ifdef WINNT
            else if (*dp == '\\')
                *dp = '/';
#endif /* WINNT */
            dp++;
        }
    pv[i] = 0;
    setq(STRpath, pv, &shvhed, VAR_READWRITE);
}

/*
 * Source to the file which is the catenation of the argument names.
 */
static int
srccat(cp, dp)
    Char   *cp, *dp;
{
    if (cp[0] == '/' && cp[1] == '\0') 
        return srcfile(short2str(dp), (mflag ? 0 : 1), 0, NULL);
    else {
        register Char *ep;
        char   *ptr;
        int rv;

#ifdef WINNT
        ep = cp;
        while(*ep)
            ep++;
        if (ep[-1] == '/' && dp[0] == '/') /* silly win95 */
            dp++;
#endif /* WINNT */

        ep = Strspl(cp, dp);
        ptr = short2str(ep);

        rv = srcfile(ptr, (mflag ? 0 : 1), 0, NULL);
        xfree((ptr_t) ep);
        return rv;
    }
}

/*
 * Source to a file putting the file descriptor in a safe place (> 2).
 */
static int
srcfile(f, onlyown, flag, av)
    char   *f;
    bool    onlyown;
    int flag;
    Char **av;
{
    register int unit;

    if ((unit = open(f, O_RDONLY)) == -1) 
        return 0;
    unit = dmove(unit, -1);

    (void) close_on_exec(unit, 1);
    srcunit(unit, onlyown, flag, av);
    return 1;
}


/*
 * Save the shell state, and establish new argument vector, and new input
 * fd.
 */
static void
st_save(st, unit, hflg, al, av)
    struct saved_state *st;
    int unit, hflg;
    Char **al, **av;
{
    st->insource        = insource;
    st->SHIN            = SHIN;
    st->intty           = intty;
    st->whyles          = whyles;
    st->gointr          = gointr;
    st->arginp          = arginp;
    st->evalp           = evalp;
    st->evalvec         = evalvec;
    st->alvecp          = alvecp;
    st->alvec           = alvec;
    st->onelflg         = onelflg;
    st->enterhist       = enterhist;
    if (hflg)
        st->HIST        = HIST;
    else
        st->HIST        = '\0';
    st->cantell         = cantell;
    cpybin(st->B, B);

    /*
     * we can now pass arguments to source. 
     * For compatibility we do that only if arguments were really
     * passed, otherwise we keep the old, global $argv like before.
     */
    if (av != NULL && *av != NULL) {
        struct varent *vp;
        if ((vp = adrof(STRargv)) != NULL)
            st->argv = saveblk(vp->vec);
        else
            st->argv = NULL;
        setq(STRargv, saveblk(av), &shvhed, VAR_READWRITE);
    }
    else
        st->argv = NULL;

    SHIN        = unit; /* Do this first */

    /* Establish new input arena */
    {
        fbuf = NULL;
        fseekp = feobp = fblocks = 0;
        settell();
    }

    arginp      = 0;
    onelflg     = 0;
    intty       = isatty(SHIN);
    whyles      = 0;
    gointr      = 0;
    evalvec     = 0;
    evalp       = 0;
    alvec       = al;
    alvecp      = 0;
    enterhist   = hflg;
    if (enterhist)
        HIST    = '\0';
    insource    = 1;
}


/*
 * Restore the shell to a saved state
 */
static void
st_restore(st, av)
    struct saved_state *st;
    Char **av;
{
    if (st->SHIN == -1)
        return;

    /* Reset input arena */
    {
        register int i;
        register Char** nfbuf = fbuf;
        register int nfblocks = fblocks;

        fblocks = 0;
        fbuf = NULL;
        for (i = 0; i < nfblocks; i++)
            xfree((ptr_t) nfbuf[i]);
        xfree((ptr_t) nfbuf);
    }
    cpybin(B, st->B);

    (void) close(SHIN);

    insource    = st->insource;
    SHIN        = st->SHIN;
    arginp      = st->arginp;
    onelflg     = st->onelflg;
    evalp       = st->evalp;
    evalvec     = st->evalvec;
    alvecp      = st->alvecp;
    alvec       = st->alvec;
    intty       = st->intty;
    whyles      = st->whyles;
    gointr      = st->gointr;
    if (st->HIST != '\0')
        HIST    = st->HIST;
    enterhist   = st->enterhist;
    cantell     = st->cantell;

    if (st->argv != NULL)
        setq(STRargv, st->argv, &shvhed, VAR_READWRITE);
    else if (av != NULL  && *av != NULL && adrof(STRargv) != NULL)
        unsetv(STRargv);
}

/*
 * Source to a unit.  If onlyown it must be our file or our group or
 * we don't chance it.  This occurs on ".cshrc"s and the like.
 */
static void
srcunit(unit, onlyown, hflg, av)
    register int unit;
    bool    onlyown;
    int hflg;
    Char **av;
{
    struct saved_state st;
    st.SHIN = -1;       /* st_restore checks this */

    if (unit < 0)
        return;

    if (didfds)
        donefds();

    if (onlyown) {
        struct stat stb;

        if (fstat(unit, &stb) < 0) {
            (void) close(unit);
            return;
        }
    }

    getexit(st.oldexit);

    if (setintr)
#ifdef BSDSIGS
        st.mask = sigblock(sigmask(SIGINT));
#else
        (void) sighold(SIGINT);
#endif

    /* Save the current state and move us to a new state */
    st_save(&st, unit, hflg, NULL, av);

    /*
     * Now if we are allowing commands to be interrupted, we let ourselves be
     * interrupted.
     */
    if (setintr)
#ifdef BSDSIGS
        (void) sigsetmask(st.mask);
#else
        (void) sigrelse(SIGINT);
#endif

    /*
     * Bugfix for running out of memory by: Jak Kirman
     * <jak%cs.brown.edu@RELAY.CS.NET>.  Solution: pay attention to what
     * setexit() is returning because reenter _may_ be in a register, and
     * thus restored to 0 on a longjump(). (PWP: insert flames about
     * compiler-dependant code here) PWP: THANKS LOTS !!!
     *
     * PWP: think of this as like a LISP (unwind-protect ...)
     * thanks to Diana Smetters for pointing out how this _should_ be written
     */
#ifdef cray
    st.reenter = 1;             /* assume non-zero return val */
    if (setexit() == 0) {
        st.reenter = 0;         /* Oh well, we were wrong */
#else
    if ((st.reenter = setexit()) == 0) {
#endif
        process(0);             /* 0 -> blow away on errors */
    }

    if (setintr)
#ifdef BSDSIGS
        (void) sigsetmask(st.mask);
#else
        (void) sigrelse(SIGINT);
#endif

    /* Restore the old state */
    st_restore(&st, av);
    resexit(st.oldexit);
    /*
     * If process reset() (effectively an unwind) then we must also unwind.
     */
    if (st.reenter)
        stderror(ERR_SILENT);
}


/*ARGSUSED*/
void
goodbye(v, c)
    Char **v;
    struct command *c;
{
    USE(c);
    record();

    if (loginsh) {
        (void) sigset(SIGQUIT, SIG_IGN);
        (void) sigset(SIGINT, SIG_IGN);
        (void) sigset(SIGTERM, SIG_IGN);
        (void) sigset(SIGHUP, SIG_IGN);
        setintr = 0;            /* No interrupts after "logout" */
        /* Trap errors inside .logout */
        reenter = setexit();
        if (reenter != 0)
            exitstat();
        if (!(adrof(STRlogout)))
            set(STRlogout, Strsave(STRnormal), VAR_READWRITE);
#ifdef _PATH_DOTLOGOUT
        (void) srcfile(_PATH_DOTLOGOUT, 0, 0, NULL);
#endif
        if (adrof(STRhome))
            (void) srccat(varval(STRhome), STRsldtlogout);
#ifdef TESLA
        do_logout = 1;
#endif /* TESLA */
    }
    exitstat();
}

void
exitstat()
{
#ifdef PROF
    monitor(0);
#endif
    /*
     * Note that if STATUS is corrupted (i.e. getn bombs) then error will exit
     * directly because we poke child here. Otherwise we might continue
     * unwarrantedly (sic).
     */
    child = 1;

    xexit(getn(varval(STRstatus)));
}

/*
 * in the event of a HUP we want to save the history
 */
static  sigret_t
phup(snum)
int snum;
{
    /*
     * There is no return from here,
     * so we are not going to release SIGHUP
     * anymore
     */
#ifdef UNRELSIGS
    if (snum)
        (void) sigset(snum, SIG_IGN);
#else
# ifdef BSDSIGS
    (void) sigblock(sigmask(SIGHUP));
# else
    (void) sighold(SIGHUP);
# endif /* BSDSIGS */
#endif /* UNRELSIGS */

    if (loginsh) {
        set(STRlogout, Strsave(STRhangup), VAR_READWRITE);
#ifdef _PATH_DOTLOGOUT
        (void) srcfile(_PATH_DOTLOGOUT, 0, 0, NULL);
#endif
        if (adrof(STRhome))
            (void) srccat(varval(STRhome), STRsldtlogout);
    }

    record();

#ifdef POSIXJOBS 
    /*
     * We kill the last foreground process group. It then becomes
     * responsible to propagate the SIGHUP to its progeny. 
     */
    {
        struct process *pp, *np;

        for (pp = proclist.p_next; pp; pp = pp->p_next) {
            np = pp;
            /* 
             * Find if this job is in the foreground. It could be that
             * the process leader has exited and the foreground flag
             * is cleared for it.
             */
            do 
                /*
                 * If a process is in the foreground we try to kill
                 * it's process group. If we succeed, then the 
                 * whole job is gone. Otherwise we keep going...
                 * But avoid sending HUP to the shell again.
                 */
                if (((np->p_flags & PFOREGND) != 0) && np->p_jobid != shpgrp) {
                    np->p_flags &= ~PHUP;
                    if (killpg(np->p_jobid, SIGHUP) != -1) {
                        /* In case the job was suspended... */
#ifdef SIGCONT
                        (void) killpg(np->p_jobid, SIGCONT);
#endif
                        break;
                    }
                }
            while ((np = np->p_friends) != pp);
        }
    }
#endif /* POSIXJOBS */

    xexit(snum);
#ifndef SIGVOID
    return (snum);
#endif
}

static Char   *jobargv[2] = {STRjobs, 0};

/*
 * Catch an interrupt, e.g. during lexical input.
 * If we are an interactive shell, we reset the interrupt catch
 * immediately.  In any case we drain the shell output,
 * and finally go through the normal error mechanism, which
 * gets a chance to make the shell go away.
 */
int     just_signaled;          /* bugfix by Michael Bloom (mg@ttidca.TTI.COM) */

#ifdef SIGVOID
/*ARGSUSED*/
#endif
sigret_t
pintr(snum)
int snum;
{
#ifdef UNRELSIGS
    if (snum)
        (void) sigset(snum, pintr);
#endif /* UNRELSIGS */
    just_signaled = 1;
    pintr1(1);
#ifndef SIGVOID
    return (snum);
#endif
}

void
pintr1(wantnl)
    bool    wantnl;
{
    register Char **v;
#ifdef BSDSIGS
    sigmask_t omask;
#endif

#ifdef BSDSIGS
    omask = sigblock((sigmask_t) 0);
#endif
    if (setintr) {
#ifdef BSDSIGS
        (void) sigsetmask(omask & ~sigmask(SIGINT));
#else
        (void) sigrelse(SIGINT);
#endif
        if (pjobs) {
            pjobs = 0;
            xputchar('\n');
            dojobs(jobargv, NULL);
            stderror(ERR_NAME | ERR_INTR);
        }
    }
    /* MH - handle interrupted completions specially */
    {
        extern int InsideCompletion;

        if (InsideCompletion)
            stderror(ERR_SILENT);
    }
    /* JV - Make sure we shut off inputl */
    {
        extern Char GettingInput;

        (void) Cookedmode();
        GettingInput = 0;
    }
#ifdef BSDSIGS
    (void) sigsetmask(omask & ~sigmask(SIGCHLD));
#else
    if (setintr)
        (void) sighold(SIGINT);
    (void) sigrelse(SIGCHLD);
#endif
    draino();
#if !defined(_VMS_POSIX) && !defined(WINNT)
    (void) endpwent();
#endif /* !_VMS_POSIX && !WINNT */

    /*
     * If we have an active "onintr" then we search for the label. Note that if
     * one does "onintr -" then we shan't be interruptible so we needn't worry
     * about that here.
     */
    if (gointr) {
        gotolab(gointr);
        timflg = 0;
        if ((v = pargv) != 0)
            pargv = 0, blkfree(v);
        if ((v = gargv) != 0)
            gargv = 0, blkfree(v);
        reset();
    }
    else if (intty && wantnl) {
        if (editing) {
            /* 
             * If we are editing a multi-line input command, and move to
             * the beginning of the line, we don't want to trash it when
             * we hit ^C
             */
            PastBottom();
            ClearLines();
            ClearDisp();
        }
        else {
            /* xputchar('\n'); *//* Some like this, others don't */
            (void) putraw('\r');
            (void) putraw('\n');
        }
    }
    stderror(ERR_SILENT);
}

/*
 * Process is the main driving routine for the shell.
 * It runs all command processing, except for those within { ... }
 * in expressions (which is run by a routine evalav in sh.exp.c which
 * is a stripped down process), and `...` evaluation which is run
 * also by a subset of this code in sh.glob.c in the routine backeval.
 *
 * The code here is a little strange because part of it is interruptible
 * and hence freeing of structures appears to occur when none is necessary
 * if this is ignored.
 *
 * Note that if catch is not set then we will unwind on any error.
 * If an end-of-file occurs, we return.
 */
static struct command *savet = NULL;
void
process(catch)
    bool    catch;
{
    extern char Expand;
    jmp_buf_t osetexit;
    /* PWP: This might get nuked my longjmp so don't make it a register var */
    struct command *t = savet;

    savet = NULL;
    getexit(osetexit);
    for (;;) {

        pendjob();

        /* This was leaking memory badly, particularly when sourcing
         * files, etc.. For whatever reason we were arriving here with
         * allocated pointers still active, and the code was simply
         * overwriting them.  I can't say I fully understand the
         * control flow here, but according to Purify this particular
         * leak has been plugged, and I haven't noticed any ill
         * effects.. (sg)
         */
        if (paraml.next && paraml.next != &paraml)
            freelex(&paraml);

        paraml.next = paraml.prev = &paraml;
        paraml.word = STRNULL;
        (void) setexit();
        justpr = enterhist;     /* execute if not entering history */

        /*
         * Interruptible during interactive reads
         */
        if (setintr)
#ifdef BSDSIGS
            (void) sigsetmask(sigblock((sigmask_t) 0) & ~sigmask(SIGINT));
#else
            (void) sigrelse(SIGINT);
#endif


        /*
         * For the sake of reset()
         */
        freelex(&paraml);
        if (savet)
            freesyn(savet), savet = NULL;

        if (haderr) {
            if (!catch) {
                /* unwind */
                doneinp = 0;
                savet = t;
                resexit(osetexit);
                reset();
            }
            haderr = 0;
            /*
             * Every error is eventually caught here or the shell dies.  It is
             * at this point that we clean up any left-over open files, by
             * closing all but a fixed number of pre-defined files.  Thus
             * routines don't have to worry about leaving files open due to
             * deeper errors... they will get closed here.
             */
            closem();
            continue;
        }
        if (doneinp) {
            doneinp = 0;
            break;
        }
        if (chkstop)
            chkstop--;
        if (neednote)
            pnote();
        if (intty && prompt && evalvec == 0) {
            just_signaled = 0;
            mailchk();
            /*
             * Watch for logins/logouts. Next is scheduled commands stored
             * previously using "sched." Then execute periodic commands.
             * Following that, the prompt precmd is run.
             */
#ifndef HAVENOUTMP
            watch_login(0);
#endif /* !HAVENOUTMP */
            sched_run(0);
            period_cmd();
            precmd();
            /*
             * If we are at the end of the input buffer then we are going to
             * read fresh stuff. Otherwise, we are rereading input and don't
             * need or want to prompt.
             */
            if (fseekp == feobp && aret == F_SEEK)
                printprompt(0, NULL);
            flush();
            setalarm(1);
        }
        if (seterr) {
            xfree((ptr_t) seterr);
            seterr = NULL;
        }

        /*
         * Echo not only on VERBOSE, but also with history expansion. If there
         * is a lexical error then we forego history echo.
         */
        if ((lex(&paraml) && !seterr && intty && !tellwhat && !Expand && 
             !whyles) || adrof(STRverbose)) {
            haderr = 1;
            prlex(&paraml);
            haderr = 0;
        }
        (void) alarm(0);        /* Autologout OFF */

        /*
         * The parser may lose space if interrupted.
         */
        if (setintr)
#ifdef BSDSIGS
            (void) sigblock(sigmask(SIGINT));
#else
            (void) sighold(SIGINT);
#endif

        /*
         * Save input text on the history list if reading in old history, or it
         * is from the terminal at the top level and not in a loop.
         * 
         * PWP: entry of items in the history list while in a while loop is done
         * elsewhere...
         */
        if (enterhist || (catch && intty && !whyles && !tellwhat && !arun))
            savehist(&paraml, enterhist > 1);

        if (Expand && seterr)
            Expand = 0;

        /*
         * Print lexical error messages, except when sourcing history lists.
         */
        if (!enterhist && seterr)
            stderror(ERR_OLD);

        /*
         * If had a history command :p modifier then this is as far as we
         * should go
         */
        if (justpr)
            reset();

        /*
         * If had a tellwhat from twenex() then do
         */
        if (tellwhat) {
            (void) tellmewhat(&paraml, NULL);
            reset();
        }

        alias(&paraml);

#ifdef BSDJOBS
        /*
         * If we are interactive, try to continue jobs that we have stopped
         */
        if (prompt)
            continue_jobs(&paraml);
#endif                          /* BSDJOBS */

        /*
         * Check to see if the user typed "rm * .o" or something
         */
        if (prompt)
            rmstar(&paraml);
        /*
         * Parse the words of the input into a parse tree.
         */
        savet = syntax(paraml.next, &paraml, 0);
        if (seterr)
            stderror(ERR_OLD);

        /*
         * Execute the parse tree From: Michael Schroeder
         * <mlschroe@immd4.informatik.uni-erlangen.de> was execute(t, tpgrp);
         */
        execute(savet, (tpgrp > 0 ? tpgrp : -1), NULL, NULL);

        /*
         * Made it!
         */
        freelex(&paraml);
        freesyn(savet), savet = NULL;
#ifdef SIG_WINDOW
        if (catch && intty && !whyles && !tellwhat)
            (void) window_change(0);    /* for window systems */
#endif /* SIG_WINDOW */
    }
    savet = t;
    resexit(osetexit);
}

/*ARGSUSED*/
void
dosource(t, c)
    register Char **t;
    struct command *c;
{
    register Char *f;
    bool    hflg = 0;
    extern int bequiet;
    char    buf[BUFSIZE];

    USE(c);
    t++;
    if (*t && eq(*t, STRmh)) {
        if (*++t == NULL)
            stderror(ERR_NAME | ERR_HFLAG);
        hflg++;
    }
    else if (*t && eq(*t, STRmm)) {
        if (*++t == NULL)
            stderror(ERR_NAME | ERR_MFLAG);
        hflg = 2;
    }

    f = globone(*t++, G_ERROR);
    (void) strcpy(buf, short2str(f));
    xfree((ptr_t) f);
    if ((!srcfile(buf, 0, hflg, t)) && (!hflg) && (!bequiet))
        stderror(ERR_SYSTEM, buf, strerror(errno));
}

/*
 * Check for mail.
 * If we are a login shell, then we don't want to tell
 * about any mail file unless its been modified
 * after the time we started.
 * This prevents us from telling the user things he already
 * knows, since the login program insists on saying
 * "You have mail."
 */

/*
 * The AMS version.
 * This version checks if the file is a directory, and if so,
 * tells you the number of files in it, otherwise do the old thang.
 * The magic "+1" in the time calculation is to compensate for
 * an AFS bug where directory mtimes are set to 1 second in
 * the future.
 */

static void
mailchk()
{
    register struct varent *v;
    register Char **vp;
    time_t  t;
    int     intvl, cnt;
    struct stat stb;
    bool    new;

    v = adrof(STRmail);
    if (v == 0)
        return;
    (void) time(&t);
    vp = v->vec;
    cnt = blklen(vp);
    intvl = (cnt && number(*vp)) ? (--cnt, getn(*vp++)) : MAILINTVL;
    if (intvl < 1)
        intvl = 1;
    if (chktim + intvl > t)
        return;
    for (; *vp; vp++) {
        char *filename = short2str(*vp);
        char *mboxdir = filename;

        if (stat(filename, &stb) < 0)
            continue;
#if defined(BSDTIMES) || defined(_SEQUENT_)
        new = stb.st_mtime > time0.tv_sec;
#else
        new = stb.st_mtime > time0;
#endif
        if (S_ISDIR(stb.st_mode)) {
            DIR *mailbox;
            int mailcount = 0;
            char tempfilename[MAXPATHLEN];
            struct stat stc;

            xsnprintf(tempfilename, MAXPATHLEN, "%s/new", filename);

            if (stat(tempfilename, &stc) != -1 && S_ISDIR(stc.st_mode)) {
                /*
                 * "filename/new" exists and is a directory; you are
                 * using Qmail.
                 */
                stb = stc;
#if defined(BSDTIMES) || defined(_SEQUENT_)
                new = stb.st_mtime > time0.tv_sec;
#else
                new = stb.st_mtime > time0;
#endif
                mboxdir = tempfilename;
            }

            if (stb.st_mtime <= chktim + 1 || (loginsh && !new))
                continue;

            if ((mailbox = opendir(mboxdir)) == NULL)
                continue;

            /* skip . and .. */
            if (!readdir(mailbox) || !readdir(mailbox))
                continue;

            while (readdir(mailbox))
                mailcount++;

            if (mailcount == 0)
                continue;

            if (cnt == 1)
                xprintf(CGETS(11, 3, "You have %d mail messages.\n"),
                        mailcount);
            else
                xprintf(CGETS(11, 4, "You have %d mail messages in %s.\n"),
                        mailcount, filename);
        }
        else {
            if (stb.st_size == 0 || stb.st_atime > stb.st_mtime ||
                (stb.st_atime <= chktim && stb.st_mtime <= chktim) ||
                (loginsh && !new))
                continue;
            if (cnt == 1)
                xprintf(CGETS(11, 5, "You have %smail.\n"),
                        new ? CGETS(11, 6, "new ") : "");
            else
                xprintf(CGETS(11, 7, "You have %smail in %s.\n"),
                        new ? CGETS(11, 6, "new ") : "", filename);
        }
    }
    chktim = t;
}

/*
 * Extract a home directory from the password file
 * The argument points to a buffer where the name of the
 * user whose home directory is sought is currently.
 * We write the home directory of the user back there.
 */
int
gethdir(home)
    Char   *home;
{
    Char   *h;

    /*
     * Is it us?
     */
    if (*home == '\0') {
        if ((h = varval(STRhome)) != STRNULL) {
            (void) Strcpy(home, h);
            return 0;
        }
        else
            return 1;
    }

    /*
     * Look in the cache
     */
    if ((h = gettilde(home)) == NULL)
        return 1;
    else {
        (void) Strcpy(home, h);
        return 0;
    }
}

/*
 * Move the initial descriptors to their eventual
 * resting places, closing all other units.
 */
void
initdesc()
{

    didfds = 0;                 /* 0, 1, 2 aren't set up */
    (void) close_on_exec(SHIN = dcopy(0, FSHIN), 1);
    (void) close_on_exec(SHOUT = dcopy(1, FSHOUT), 1);
    (void) close_on_exec(SHDIAG = dcopy(2, FSHDIAG), 1);
    (void) close_on_exec(OLDSTD = dcopy(SHIN, FOLDSTD), 1);
#ifndef CLOSE_ON_EXEC
    didcch = 0;                 /* Havent closed for child */
#endif /* CLOSE_ON_EXEC */
    isdiagatty = isatty(SHDIAG);
    isoutatty = isatty(SHOUT);
    closem();
}


void
#ifdef PROF
done(i)
#else
xexit(i)
#endif
    int     i;
{
#ifdef TESLA
    if (loginsh && do_logout) {
        /* this is to send hangup signal to the develcon */
        /* we toggle DTR. clear dtr - sleep 1 - set dtr */
        /* ioctl will return ENOTTY for pty's but we ignore it   */
        /* exitstat will run after disconnect */
        /* we sleep for 2 seconds to let things happen in */
        /* .logout and rechist() */
#ifdef TIOCCDTR
        (void) sleep(2);
        (void) ioctl(FSHTTY, TIOCCDTR, NULL);
        (void) sleep(1);
        (void) ioctl(FSHTTY, TIOCSDTR, NULL);
#endif /* TIOCCDTR */
    }
#endif /* TESLA */

    {
        struct process *pp, *np;

        /* Kill all processes marked for hup'ing */
        for (pp = proclist.p_next; pp; pp = pp->p_next) {
            np = pp;
            do 
                if ((np->p_flags & PHUP) && np->p_jobid != shpgrp) {
                    if (killpg(np->p_jobid, SIGHUP) != -1) {
                        /* In case the job was suspended... */
#ifdef SIGCONT
                        (void) killpg(np->p_jobid, SIGCONT);
#endif
                        break;
                    }
                }
            while ((np = np->p_friends) != pp);
        }
    }
    untty();
#ifdef NLS_CATALOGS
    /*
     * We need to call catclose, because SVR4 leaves symlinks behind otherwise
     * in the catalog directories. We cannot close on a vforked() child,
     * because messages will stop working on the parent too.
     */
    if (child == 0)
        (void) catclose(catd);
#endif /* NLS_CATALOGS */
#ifdef WINNT
    nt_cleanup();
#endif /* WINNT */
    _exit(i);
}

#ifndef _PATH_DEFPATH
static Char **
defaultpath()
{
    char   *ptr;
    Char  **blk, **blkp;
    struct stat stb;

    blkp = blk = (Char **) xmalloc((size_t) sizeof(Char *) * 10);

#ifndef NODOT
# ifndef DOTLAST
    *blkp++ = Strsave(STRdot);
# endif
#endif

#define DIRAPPEND(a)  \
        if (stat(ptr = a, &stb) == 0 && S_ISDIR(stb.st_mode)) \
                *blkp++ = SAVE(ptr)

#ifdef _PATH_LOCAL
    DIRAPPEND(_PATH_LOCAL);
#endif

#ifdef _PATH_USRUCB
    DIRAPPEND(_PATH_USRUCB);
#endif

#ifdef _PATH_USRBSD
    DIRAPPEND(_PATH_USRBSD);
#endif

#ifdef _PATH_BIN
    DIRAPPEND(_PATH_BIN);
#endif

#ifdef _PATH_USRBIN
    DIRAPPEND(_PATH_USRBIN);
#endif

#undef DIRAPPEND

#ifndef NODOT
# ifdef DOTLAST
    *blkp++ = Strsave(STRdot);
# endif
#endif
    *blkp = NULL;
    return (blk);
}
#endif

static void
record()
{
    if (!fast) {
        recdirs(NULL, adrof(STRsavedirs) != NULL);
        rechist(NULL, adrof(STRsavehist) != NULL);
    }
}