source: trunk/third/perl/doio.c @ 13842

/*    doio.c
 *
 *    Copyright (c) 1991-1997, Larry Wall
 *
 *    You may distribute under the terms of either the GNU General Public
 *    License or the Artistic License, as specified in the README file.
 *
 */

/*
 * "Far below them they saw the white waters pour into a foaming bowl, and
 * then swirl darkly about a deep oval basin in the rocks, until they found
 * their way out again through a narrow gate, and flowed away, fuming and
 * chattering, into calmer and more level reaches."
 */

#include "EXTERN.h"
#include "perl.h"

#if defined(HAS_MSG) || defined(HAS_SEM) || defined(HAS_SHM)
#include <sys/ipc.h>
#ifdef HAS_MSG
#include <sys/msg.h>
#endif
#ifdef HAS_SEM
#include <sys/sem.h>
#endif
#ifdef HAS_SHM
#include <sys/shm.h>
# ifndef HAS_SHMAT_PROTOTYPE
    extern Shmat_t shmat _((int, char *, int));
# endif
#endif
#endif

#ifdef _SEM_SEMUN_UNDEFINED
/* Added by tb@mit.edu 25 Oct 1999 for Athena. */
union semun
   {
     int val;
     struct semid_ds *buf;
     unsigned short int *array;
     struct seminfo *__buf;
   };
#endif

#ifdef I_UTIME
#  ifdef _MSC_VER
#    include <sys/utime.h>
#  else
#    include <utime.h>
#  endif
#endif
#ifdef I_FCNTL
#include <fcntl.h>
#endif
#ifdef I_SYS_FILE
#include <sys/file.h>
#endif

#if !defined(NSIG) || defined(M_UNIX) || defined(M_XENIX)
#include <signal.h>
#endif

/* XXX If this causes problems, set i_unistd=undef in the hint file.  */
#ifdef I_UNISTD
#  include <unistd.h>
#endif

#if defined(HAS_SOCKET) && !defined(VMS) /* VMS handles sockets via vmsish.h */
# include <sys/socket.h>
# include <netdb.h>
# ifndef ENOTSOCK
#  ifdef I_NET_ERRNO
#   include <net/errno.h>
#  endif
# endif
#endif

/* Put this after #includes because <unistd.h> defines _XOPEN_*. */
#ifndef Sock_size_t
#  if _XOPEN_VERSION >= 5 || defined(_XOPEN_SOURCE_EXTENDED) || defined(__GLIBC__)
#    define Sock_size_t Size_t
#  else
#    define Sock_size_t int
#  endif
#endif

bool
do_open(gv,name,len,as_raw,rawmode,rawperm,supplied_fp)
GV *gv;
register char *name;
I32 len;
int as_raw;
int rawmode, rawperm;
PerlIO *supplied_fp;
{
    register IO *io = GvIOn(gv);
    PerlIO *saveifp = Nullfp;
    PerlIO *saveofp = Nullfp;
    char savetype = ' ';
    int writing = 0;
    PerlIO *fp;
    int fd;
    int result;

    forkprocess = 1;            /* assume true if no fork */

    if (IoIFP(io)) {
        fd = PerlIO_fileno(IoIFP(io));
        if (IoTYPE(io) == '-')
            result = 0;
        else if (fd <= maxsysfd) {
            saveifp = IoIFP(io);
            saveofp = IoOFP(io);
            savetype = IoTYPE(io);
            result = 0;
        }
        else if (IoTYPE(io) == '|')
            result = my_pclose(IoIFP(io));
        else if (IoIFP(io) != IoOFP(io)) {
            if (IoOFP(io)) {
                result = PerlIO_close(IoOFP(io));
                PerlIO_close(IoIFP(io));        /* clear stdio, fd already closed */
            }
            else
                result = PerlIO_close(IoIFP(io));
        }
        else
            result = PerlIO_close(IoIFP(io));
        if (result == EOF && fd > maxsysfd)
            PerlIO_printf(PerlIO_stderr(), "Warning: unable to close filehandle %s properly.\n",
              GvENAME(gv));
        IoOFP(io) = IoIFP(io) = Nullfp;
    }

    if (as_raw) {
        result = rawmode & 3;
        IoTYPE(io) = "<>++"[result];
        writing = (result > 0);
        fd = open(name, rawmode, rawperm);
        if (fd == -1)
            fp = NULL;
        else {
            char *fpmode;
            if (result == 0)
                fpmode = "r";
#ifdef O_APPEND
            else if (rawmode & O_APPEND)
                fpmode = (result == 1) ? "a" : "a+";
#endif
            else
                fpmode = (result == 1) ? "w" : "r+";
            fp = PerlIO_fdopen(fd, fpmode);
            if (!fp)
                close(fd);
        }
    }
    else {
        char *myname;
        char mode[3];           /* stdio file mode ("r\0" or "r+\0") */
        int dodup;

        myname = savepvn(name, len);
        SAVEFREEPV(myname);
        name = myname;
        while (len && isSPACE(name[len-1]))
            name[--len] = '\0';

        mode[0] = mode[1] = mode[2] = '\0';
        IoTYPE(io) = *name;
        if (*name == '+' && len > 1 && name[len-1] != '|') { /* scary */
            mode[1] = *name++;
            --len;
            writing = 1;
        }

        if (*name == '|') {
            /*SUPPRESS 530*/
            for (name++; isSPACE(*name); name++) ;
            if (strNE(name,"-"))
                TAINT_ENV();
            TAINT_PROPER("piped open");
            if (dowarn && name[strlen(name)-1] == '|')
                warn("Can't do bidirectional pipe");
            fp = my_popen(name,"w");
            writing = 1;
        }
        else if (*name == '>') {
            TAINT_PROPER("open");
            name++;
            if (*name == '>') {
                mode[0] = IoTYPE(io) = 'a';
                name++;
            }
            else
                mode[0] = 'w';
            writing = 1;

            if (*name == '&') {
              duplicity:
                dodup = 1;
                name++;
                if (*name == '=') {
                    dodup = 0;
                    name++;
                }
                if (!*name && supplied_fp)
                    fp = supplied_fp;
                else {
                    /*SUPPRESS 530*/
                    for (; isSPACE(*name); name++) ;
                    if (isDIGIT(*name))
                        fd = atoi(name);
                    else {
                        IO* thatio;
                        gv = gv_fetchpv(name,FALSE,SVt_PVIO);
                        thatio = GvIO(gv);
                        if (!thatio) {
#ifdef EINVAL
                            SETERRNO(EINVAL,SS$_IVCHAN);
#endif
                            goto say_false;
                        }
                        if (IoIFP(thatio)) {
                            fd = PerlIO_fileno(IoIFP(thatio));
                            if (IoTYPE(thatio) == 's')
                                IoTYPE(io) = 's';
                        }
                        else
                            fd = -1;
                    }
                    if (dodup)
                        fd = dup(fd);
                    if (!(fp = PerlIO_fdopen(fd,mode))) {
                        if (dodup)
                            close(fd);
                        }
                }
            }
            else {
                /*SUPPRESS 530*/
                for (; isSPACE(*name); name++) ;
                if (strEQ(name,"-")) {
                    fp = PerlIO_stdout();
                    IoTYPE(io) = '-';
                }
                else  {
                    fp = PerlIO_open(name,mode);
                }
            }
        }
        else if (*name == '<') {
            /*SUPPRESS 530*/
            for (name++; isSPACE(*name); name++) ;
            mode[0] = 'r';
            if (*name == '&')
                goto duplicity;
            if (strEQ(name,"-")) {
                fp = PerlIO_stdin();
                IoTYPE(io) = '-';
            }
            else
                fp = PerlIO_open(name,mode);
        }
        else if (name[len-1] == '|') {
            name[--len] = '\0';
            while (len && isSPACE(name[len-1]))
                name[--len] = '\0';
            /*SUPPRESS 530*/
            for (; isSPACE(*name); name++) ;
            if (strNE(name,"-"))
                TAINT_ENV();
            TAINT_PROPER("piped open");
            fp = my_popen(name,"r");
            IoTYPE(io) = '|';
        }
        else {
            IoTYPE(io) = '<';
            /*SUPPRESS 530*/
            for (; isSPACE(*name); name++) ;
            if (strEQ(name,"-")) {
                fp = PerlIO_stdin();
                IoTYPE(io) = '-';
            }
            else
                fp = PerlIO_open(name,"r");
        }
    }
    if (!fp) {
        if (dowarn && IoTYPE(io) == '<' && strchr(name, '\n'))
            warn(warn_nl, "open");
        goto say_false;
    }
    if (IoTYPE(io) &&
      IoTYPE(io) != '|' && IoTYPE(io) != '-') {
        if (Fstat(PerlIO_fileno(fp),&statbuf) < 0) {
            (void)PerlIO_close(fp);
            goto say_false;
        }
        if (S_ISSOCK(statbuf.st_mode))
            IoTYPE(io) = 's';   /* in case a socket was passed in to us */
#ifdef HAS_SOCKET
        else if (
#ifdef S_IFMT
            !(statbuf.st_mode & S_IFMT)
#else
            !statbuf.st_mode
#endif
        ) {
            Sock_size_t buflen = sizeof tokenbuf;
            if (getsockname(PerlIO_fileno(fp), (struct sockaddr *)tokenbuf,
                            &buflen) >= 0
                  || errno != ENOTSOCK)
                IoTYPE(io) = 's'; /* some OS's return 0 on fstat()ed socket */
                                /* but some return 0 for streams too, sigh */
        }
#endif
    }
    if (saveifp) {              /* must use old fp? */
        fd = PerlIO_fileno(saveifp);
        if (saveofp) {
            PerlIO_flush(saveofp);              /* emulate PerlIO_close() */
            if (saveofp != saveifp) {   /* was a socket? */
                PerlIO_close(saveofp);
                if (fd > 2)
                    Safefree(saveofp);
            }
        }
        if (fd != PerlIO_fileno(fp)) {
            int pid;
            SV *sv;

            dup2(PerlIO_fileno(fp), fd);
            sv = *av_fetch(fdpid,PerlIO_fileno(fp),TRUE);
            (void)SvUPGRADE(sv, SVt_IV);
            pid = SvIVX(sv);
            SvIVX(sv) = 0;
            sv = *av_fetch(fdpid,fd,TRUE);
            (void)SvUPGRADE(sv, SVt_IV);
            SvIVX(sv) = pid;
            PerlIO_close(fp);

        }
        fp = saveifp;
        PerlIO_clearerr(fp);
    }
#if defined(HAS_FCNTL) && defined(F_SETFD)
    fd = PerlIO_fileno(fp);
    fcntl(fd,F_SETFD,fd > maxsysfd);
#endif
    IoIFP(io) = fp;
    if (writing) {
        if (IoTYPE(io) == 's'
          || (IoTYPE(io) == '>' && S_ISCHR(statbuf.st_mode)) ) {
            if (!(IoOFP(io) = PerlIO_fdopen(PerlIO_fileno(fp),"w"))) {
                PerlIO_close(fp);
                IoIFP(io) = Nullfp;
                goto say_false;
            }
        }
        else
            IoOFP(io) = fp;
    }
    return TRUE;

say_false:
    IoIFP(io) = saveifp;
    IoOFP(io) = saveofp;
    IoTYPE(io) = savetype;
    return FALSE;
}

PerlIO *
nextargv(gv)
register GV *gv;
{
    register SV *sv;
#ifndef FLEXFILENAMES
    int filedev;
    int fileino;
#endif
    int fileuid;
    int filegid;

    if (!argvoutgv)
        argvoutgv = gv_fetchpv("ARGVOUT",TRUE,SVt_PVIO);
    if (filemode & (S_ISUID|S_ISGID)) {
        PerlIO_flush(IoIFP(GvIOn(argvoutgv)));  /* chmod must follow last write */
#ifdef HAS_FCHMOD
        (void)fchmod(lastfd,filemode);
#else
        (void)chmod(oldname,filemode);
#endif
    }
    filemode = 0;
    while (av_len(GvAV(gv)) >= 0) {
        STRLEN len;
        sv = av_shift(GvAV(gv));
        SAVEFREESV(sv);
        sv_setsv(GvSV(gv),sv);
        SvSETMAGIC(GvSV(gv));
        oldname = SvPVx(GvSV(gv), len);
        if (do_open(gv,oldname,len,FALSE,0,0,Nullfp)) {
            if (inplace) {
                TAINT_PROPER("inplace open");
                if (strEQ(oldname,"-")) {
                    setdefout(gv_fetchpv("STDOUT",TRUE,SVt_PVIO));
                    return IoIFP(GvIOp(gv));
                }
#ifndef FLEXFILENAMES
                filedev = statbuf.st_dev;
                fileino = statbuf.st_ino;
#endif
                filemode = statbuf.st_mode;
                fileuid = statbuf.st_uid;
                filegid = statbuf.st_gid;
                if (!S_ISREG(filemode)) {
                    warn("Can't do inplace edit: %s is not a regular file",
                      oldname );
                    do_close(gv,FALSE);
                    continue;
                }
                if (*inplace) {
#ifdef SUFFIX
                    add_suffix(sv,inplace);
#else
                    sv_catpv(sv,inplace);
#endif
#ifndef FLEXFILENAMES
                    if (Stat(SvPVX(sv),&statbuf) >= 0
                      && statbuf.st_dev == filedev
                      && statbuf.st_ino == fileino ) {
                        warn("Can't do inplace edit: %s > 14 characters",
                          SvPVX(sv) );
                        do_close(gv,FALSE);
                        continue;
                    }
#endif
#ifdef HAS_RENAME
#ifndef DOSISH
                    if (rename(oldname,SvPVX(sv)) < 0) {
                        warn("Can't rename %s to %s: %s, skipping file",
                          oldname, SvPVX(sv), Strerror(errno) );
                        do_close(gv,FALSE);
                        continue;
                    }
#else
                    do_close(gv,FALSE);
                    (void)unlink(SvPVX(sv));
                    (void)rename(oldname,SvPVX(sv));
                    do_open(gv,SvPVX(sv),SvCUR(sv),FALSE,0,0,Nullfp);
#endif /* DOSISH */
#else
                    (void)UNLINK(SvPVX(sv));
                    if (link(oldname,SvPVX(sv)) < 0) {
                        warn("Can't rename %s to %s: %s, skipping file",
                          oldname, SvPVX(sv), Strerror(errno) );
                        do_close(gv,FALSE);
                        continue;
                    }
                    (void)UNLINK(oldname);
#endif
                }
                else {
#if !defined(DOSISH) && !defined(AMIGAOS)
#  ifndef VMS  /* Don't delete; use automatic file versioning */
                    if (UNLINK(oldname) < 0) {
                        warn("Can't rename %s to %s: %s, skipping file",
                          oldname, SvPVX(sv), Strerror(errno) );
                        do_close(gv,FALSE);
                        continue;
                    }
#  endif
#else
                    croak("Can't do inplace edit without backup");
#endif
                }

                sv_setpvn(sv,">",1);
                sv_catpv(sv,oldname);
                SETERRNO(0,0);          /* in case sprintf set errno */
                if (!do_open(argvoutgv,SvPVX(sv),SvCUR(sv),FALSE,0,0,Nullfp)) {
                    warn("Can't do inplace edit on %s: %s",
                      oldname, Strerror(errno) );
                    do_close(gv,FALSE);
                    continue;
                }
                setdefout(argvoutgv);
                lastfd = PerlIO_fileno(IoIFP(GvIOp(argvoutgv)));
                (void)Fstat(lastfd,&statbuf);
#ifdef HAS_FCHMOD
                (void)fchmod(lastfd,filemode);
#else
#  if !(defined(WIN32) && defined(__BORLANDC__))
                /* Borland runtime creates a readonly file! */
                (void)chmod(oldname,filemode);
#  endif
#endif
                if (fileuid != statbuf.st_uid || filegid != statbuf.st_gid) {
#ifdef HAS_FCHOWN
                    (void)fchown(lastfd,fileuid,filegid);
#else
#ifdef HAS_CHOWN
                    (void)chown(oldname,fileuid,filegid);
#endif
#endif
                }
            }
            return IoIFP(GvIOp(gv));
        }
        else
            PerlIO_printf(PerlIO_stderr(), "Can't open %s: %s\n",SvPV(sv, na), Strerror(errno));
    }
    if (inplace) {
        (void)do_close(argvoutgv,FALSE);
        setdefout(gv_fetchpv("STDOUT",TRUE,SVt_PVIO));
    }
    return Nullfp;
}

#ifdef HAS_PIPE
void
do_pipe(sv, rgv, wgv)
SV *sv;
GV *rgv;
GV *wgv;
{
    register IO *rstio;
    register IO *wstio;
    int fd[2];

    if (!rgv)
        goto badexit;
    if (!wgv)
        goto badexit;

    rstio = GvIOn(rgv);
    wstio = GvIOn(wgv);

    if (IoIFP(rstio))
        do_close(rgv,FALSE);
    if (IoIFP(wstio))
        do_close(wgv,FALSE);

    if (pipe(fd) < 0)
        goto badexit;
    IoIFP(rstio) = PerlIO_fdopen(fd[0], "r");
    IoOFP(wstio) = PerlIO_fdopen(fd[1], "w");
    IoIFP(wstio) = IoOFP(wstio);
    IoTYPE(rstio) = '<';
    IoTYPE(wstio) = '>';
    if (!IoIFP(rstio) || !IoOFP(wstio)) {
        if (IoIFP(rstio)) PerlIO_close(IoIFP(rstio));
        else close(fd[0]);
        if (IoOFP(wstio)) PerlIO_close(IoOFP(wstio));
        else close(fd[1]);
        goto badexit;
    }

    sv_setsv(sv,&sv_yes);
    return;

badexit:
    sv_setsv(sv,&sv_undef);
    return;
}
#endif

/* explicit renamed to avoid C++ conflict    -- kja */
bool
#ifndef CAN_PROTOTYPE
do_close(gv,not_implicit)
GV *gv;
bool not_implicit;
#else
do_close(GV *gv, bool not_implicit)
#endif /* CAN_PROTOTYPE */
{
    bool retval;
    IO *io;

    if (!gv)
        gv = argvgv;
    if (!gv || SvTYPE(gv) != SVt_PVGV) {
        SETERRNO(EBADF,SS$_IVCHAN);
        return FALSE;
    }
    io = GvIO(gv);
    if (!io) {          /* never opened */
        if (dowarn && not_implicit)
            warn("Close on unopened file <%s>",GvENAME(gv));
        return FALSE;
    }
    retval = io_close(io);
    if (not_implicit) {
        IoLINES(io) = 0;
        IoPAGE(io) = 0;
        IoLINES_LEFT(io) = IoPAGE_LEN(io);
    }
    IoTYPE(io) = ' ';
    return retval;
}

bool
io_close(io)
IO* io;
{
    bool retval = FALSE;
    int status;

    if (IoIFP(io)) {
        if (IoTYPE(io) == '|') {
            status = my_pclose(IoIFP(io));
            STATUS_NATIVE_SET(status);
            retval = (STATUS_POSIX == 0);
        }
        else if (IoTYPE(io) == '-')
            retval = TRUE;
        else {
            if (IoOFP(io) && IoOFP(io) != IoIFP(io)) {          /* a socket */
                retval = (PerlIO_close(IoOFP(io)) != EOF);
                PerlIO_close(IoIFP(io));        /* clear stdio, fd already closed */
            }
            else
                retval = (PerlIO_close(IoIFP(io)) != EOF);
        }
        IoOFP(io) = IoIFP(io) = Nullfp;
    }

    return retval;
}

bool
do_eof(gv)
GV *gv;
{
    register IO *io;
    int ch;

    io = GvIO(gv);

    if (!io)
        return TRUE;

    while (IoIFP(io)) {

        if (PerlIO_has_cntptr(IoIFP(io))) {     /* (the code works without this) */
            if (PerlIO_get_cnt(IoIFP(io)) > 0)  /* cheat a little, since */
                return FALSE;                   /* this is the most usual case */
        }

        ch = PerlIO_getc(IoIFP(io));
        if (ch != EOF) {
            (void)PerlIO_ungetc(IoIFP(io),ch);
            return FALSE;
        }
        if (PerlIO_has_cntptr(IoIFP(io)) && PerlIO_canset_cnt(IoIFP(io))) {
            if (PerlIO_get_cnt(IoIFP(io)) < -1)
                PerlIO_set_cnt(IoIFP(io),-1);
        }
        if (op->op_flags & OPf_SPECIAL) { /* not necessarily a real EOF yet? */
            if (!nextargv(argvgv))      /* get another fp handy */
                return TRUE;
        }
        else
            return TRUE;                /* normal fp, definitely end of file */
    }
    return TRUE;
}

long
do_tell(gv)
GV *gv;
{
    register IO *io;
    register PerlIO *fp;

    if (gv && (io = GvIO(gv)) && (fp = IoIFP(io))) {
#ifdef ULTRIX_STDIO_BOTCH
        if (PerlIO_eof(fp))
            (void)PerlIO_seek(fp, 0L, 2);       /* ultrix 1.2 workaround */
#endif
        return PerlIO_tell(fp);
    }
    if (dowarn)
        warn("tell() on unopened file");
    SETERRNO(EBADF,RMS$_IFI);
    return -1L;
}

bool
do_seek(gv, pos, whence)
GV *gv;
long pos;
int whence;
{
    register IO *io;
    register PerlIO *fp;

    if (gv && (io = GvIO(gv)) && (fp = IoIFP(io))) {
#ifdef ULTRIX_STDIO_BOTCH
        if (PerlIO_eof(fp))
            (void)PerlIO_seek(fp, 0L, 2);       /* ultrix 1.2 workaround */
#endif
        return PerlIO_seek(fp, pos, whence) >= 0;
    }
    if (dowarn)
        warn("seek() on unopened file");
    SETERRNO(EBADF,RMS$_IFI);
    return FALSE;
}

long
do_sysseek(gv, pos, whence)
GV *gv;
long pos;
int whence;
{
    register IO *io;
    register PerlIO *fp;

    if (gv && (io = GvIO(gv)) && (fp = IoIFP(io)))
        return lseek(PerlIO_fileno(fp), pos, whence);
    if (dowarn)
        warn("sysseek() on unopened file");
    SETERRNO(EBADF,RMS$_IFI);
    return -1L;
}

#if !defined(HAS_TRUNCATE) && !defined(HAS_CHSIZE) && defined(F_FREESP)
        /* code courtesy of William Kucharski */
#define HAS_CHSIZE

I32 my_chsize(fd, length)
I32 fd;                 /* file descriptor */
Off_t length;           /* length to set file to */
{
    struct flock fl;
    struct stat filebuf;

    if (Fstat(fd, &filebuf) < 0)
        return -1;

    if (filebuf.st_size < length) {

        /* extend file length */

        if ((lseek(fd, (length - 1), 0)) < 0)
            return -1;

        /* write a "0" byte */

        if ((write(fd, "", 1)) != 1)
            return -1;
    }
    else {
        /* truncate length */

        fl.l_whence = 0;
        fl.l_len = 0;
        fl.l_start = length;
        fl.l_type = F_WRLCK;    /* write lock on file space */

        /*
        * This relies on the UNDOCUMENTED F_FREESP argument to
        * fcntl(2), which truncates the file so that it ends at the
        * position indicated by fl.l_start.
        *
        * Will minor miracles never cease?
        */

        if (fcntl(fd, F_FREESP, &fl) < 0)
            return -1;

    }

    return 0;
}
#endif /* F_FREESP */

bool
do_print(sv,fp)
register SV *sv;
PerlIO *fp;
{
    register char *tmps;
    STRLEN len;

    /* assuming fp is checked earlier */
    if (!sv)
        return TRUE;
    if (ofmt) {
        if (SvGMAGICAL(sv))
            mg_get(sv);
        if (SvIOK(sv) && SvIVX(sv) != 0) {
            PerlIO_printf(fp, ofmt, (double)SvIVX(sv));
            return !PerlIO_error(fp);
        }
        if (  (SvNOK(sv) && SvNVX(sv) != 0.0)
           || (looks_like_number(sv) && sv_2nv(sv) != 0.0) ) {
            PerlIO_printf(fp, ofmt, SvNVX(sv));
            return !PerlIO_error(fp);
        }
    }
    switch (SvTYPE(sv)) {
    case SVt_NULL:
        if (dowarn)
            warn(warn_uninit);
        return TRUE;
    case SVt_IV:
        if (SvIOK(sv)) {
            if (SvGMAGICAL(sv))
                mg_get(sv);
            PerlIO_printf(fp, "%ld", (long)SvIVX(sv));
            return !PerlIO_error(fp);
        }
        /* FALL THROUGH */
    default:
        tmps = SvPV(sv, len);
        break;
    }
    if (len && (PerlIO_write(fp,tmps,len) == 0 || PerlIO_error(fp)))
        return FALSE;
    return !PerlIO_error(fp);
}

I32
my_stat(ARGS)
dARGS
{
    dSP;
    IO *io;
    GV* tmpgv;

    if (op->op_flags & OPf_REF) {
        EXTEND(sp,1);
        tmpgv = cGVOP->op_gv;
      do_fstat:
        io = GvIO(tmpgv);
        if (io && IoIFP(io)) {
            statgv = tmpgv;
            sv_setpv(statname,"");
            laststype = OP_STAT;
            return (laststatval = Fstat(PerlIO_fileno(IoIFP(io)), &statcache));
        }
        else {
            if (tmpgv == defgv)
                return laststatval;
            if (dowarn)
                warn("Stat on unopened file <%s>",
                  GvENAME(tmpgv));
            statgv = Nullgv;
            sv_setpv(statname,"");
            return (laststatval = -1);
        }
    }
    else {
        SV* sv = POPs;
        PUTBACK;
        if (SvTYPE(sv) == SVt_PVGV) {
            tmpgv = (GV*)sv;
            goto do_fstat;
        }
        else if (SvROK(sv) && SvTYPE(SvRV(sv)) == SVt_PVGV) {
            tmpgv = (GV*)SvRV(sv);
            goto do_fstat;
        }

        statgv = Nullgv;
        sv_setpv(statname,SvPV(sv, na));
        laststype = OP_STAT;
        laststatval = Stat(SvPV(sv, na),&statcache);
        if (laststatval < 0 && dowarn && strchr(SvPV(sv, na), '\n'))
            warn(warn_nl, "stat");
        return laststatval;
    }
}

I32
my_lstat(ARGS)
dARGS
{
    dSP;
    SV *sv;
    if (op->op_flags & OPf_REF) {
        EXTEND(sp,1);
        if (cGVOP->op_gv == defgv) {
            if (laststype != OP_LSTAT)
                croak("The stat preceding -l _ wasn't an lstat");
            return laststatval;
        }
        croak("You can't use -l on a filehandle");
    }

    laststype = OP_LSTAT;
    statgv = Nullgv;
    sv = POPs;
    PUTBACK;
    sv_setpv(statname,SvPV(sv, na));
#ifdef HAS_LSTAT
    laststatval = lstat(SvPV(sv, na),&statcache);
#else
    laststatval = Stat(SvPV(sv, na),&statcache);
#endif
    if (laststatval < 0 && dowarn && strchr(SvPV(sv, na), '\n'))
        warn(warn_nl, "lstat");
    return laststatval;
}

bool
do_aexec(really,mark,sp)
SV *really;
register SV **mark;
register SV **sp;
{
    register char **a;
    char *tmps;

    if (sp > mark) {
        New(401,Argv, sp - mark + 1, char*);
        a = Argv;
        while (++mark <= sp) {
            if (*mark)
                *a++ = SvPVx(*mark, na);
            else
                *a++ = "";
        }
        *a = Nullch;
        if (*Argv[0] != '/')    /* will execvp use PATH? */
            TAINT_ENV();                /* testing IFS here is overkill, probably */
        if (really && *(tmps = SvPV(really, na)))
            execvp(tmps,Argv);
        else
            execvp(Argv[0],Argv);
        if (dowarn)
            warn("Can't exec \"%s\": %s", Argv[0], Strerror(errno));
    }
    do_execfree();
    return FALSE;
}

void
do_execfree()
{
    if (Argv) {
        Safefree(Argv);
        Argv = Null(char **);
    }
    if (Cmd) {
        Safefree(Cmd);
        Cmd = Nullch;
    }
}

#if !defined(OS2) && !defined(WIN32)

bool
do_exec(cmd)
char *cmd;
{
    register char **a;
    register char *s;
    char flags[10];

    while (*cmd && isSPACE(*cmd))
        cmd++;

    /* save an extra exec if possible */

#ifdef CSH
    if (strnEQ(cmd,cshname,cshlen) && strnEQ(cmd+cshlen," -c",3)) {
        strcpy(flags,"-c");
        s = cmd+cshlen+3;
        if (*s == 'f') {
            s++;
            strcat(flags,"f");
        }
        if (*s == ' ')
            s++;
        if (*s++ == '\'') {
            char *ncmd = s;

            while (*s)
                s++;
            if (s[-1] == '\n')
                *--s = '\0';
            if (s[-1] == '\'') {
                *--s = '\0';
                execl(cshname,"csh", flags,ncmd,(char*)0);
                *s = '\'';
                return FALSE;
            }
        }
    }
#endif /* CSH */

    /* see if there are shell metacharacters in it */

    if (*cmd == '.' && isSPACE(cmd[1]))
        goto doshell;

    if (strnEQ(cmd,"exec",4) && isSPACE(cmd[4]))
        goto doshell;

    for (s = cmd; *s && isALPHA(*s); s++) ;     /* catch VAR=val gizmo */
    if (*s == '=')
        goto doshell;

    for (s = cmd; *s; s++) {
        if (*s != ' ' && !isALPHA(*s) && strchr("$&*(){}[]'\";\\|?<>~`\n",*s)) {
            if (*s == '\n' && !s[1]) {
                *s = '\0';
                break;
            }
          doshell:
            execl(sh_path, "sh", "-c", cmd, (char*)0);
            return FALSE;
        }
    }

    New(402,Argv, (s - cmd) / 2 + 2, char*);
    Cmd = savepvn(cmd, s-cmd);
    a = Argv;
    for (s = Cmd; *s;) {
        while (*s && isSPACE(*s)) s++;
        if (*s)
            *(a++) = s;
        while (*s && !isSPACE(*s)) s++;
        if (*s)
            *s++ = '\0';
    }
    *a = Nullch;
    if (Argv[0]) {
        execvp(Argv[0],Argv);
        if (errno == ENOEXEC) {         /* for system V NIH syndrome */
            do_execfree();
            goto doshell;
        }
        if (dowarn)
            warn("Can't exec \"%s\": %s", Argv[0], Strerror(errno));
    }
    do_execfree();
    return FALSE;
}

#endif /* OS2 || WIN32 */

I32
apply(type,mark,sp)
I32 type;
register SV **mark;
register SV **sp;
{
    register I32 val;
    register I32 val2;
    register I32 tot = 0;
    char *s;
    SV **oldmark = mark;

    if (tainting) {
        while (++mark <= sp) {
            if (SvTAINTED(*mark)) {
                TAINT;
                break;
            }
        }
        mark = oldmark;
    }
    switch (type) {
    case OP_CHMOD:
        TAINT_PROPER("chmod");
        if (++mark <= sp) {
            tot = sp - mark;
            val = SvIVx(*mark);
            while (++mark <= sp) {
                if (chmod(SvPVx(*mark, na),val))
                    tot--;
            }
        }
        break;
#ifdef HAS_CHOWN
    case OP_CHOWN:
        TAINT_PROPER("chown");
        if (sp - mark > 2) {
            val = SvIVx(*++mark);
            val2 = SvIVx(*++mark);
            tot = sp - mark;
            while (++mark <= sp) {
                if (chown(SvPVx(*mark, na),val,val2))
                    tot--;
            }
        }
        break;
#endif
#ifdef HAS_KILL
    case OP_KILL:
        TAINT_PROPER("kill");
        if (mark == sp)
            break;
        s = SvPVx(*++mark, na);
        tot = sp - mark;
        if (isUPPER(*s)) {
            if (*s == 'S' && s[1] == 'I' && s[2] == 'G')
                s += 3;
            if (!(val = whichsig(s)))
                croak("Unrecognized signal name \"%s\"",s);
        }
        else
            val = SvIVx(*mark);
#ifdef VMS
        /* kill() doesn't do process groups (job trees?) under VMS */
        if (val < 0) val = -val;
        if (val == SIGKILL) {
#           include <starlet.h>
            /* Use native sys$delprc() to insure that target process is
             * deleted; supervisor-mode images don't pay attention to
             * CRTL's emulation of Unix-style signals and kill()
             */
            while (++mark <= sp) {
                I32 proc = SvIVx(*mark);
                register unsigned long int __vmssts;
                if (!((__vmssts = sys$delprc(&proc,0)) & 1)) {
                    tot--;
                    switch (__vmssts) {
                        case SS$_NONEXPR:
                        case SS$_NOSUCHNODE:
                            SETERRNO(ESRCH,__vmssts);
                            break;
                        case SS$_NOPRIV:
                            SETERRNO(EPERM,__vmssts);
                            break;
                        default:
                            SETERRNO(EVMSERR,__vmssts);
                    }
                }
            }
            break;
        }
#endif
        if (val < 0) {
            val = -val;
            while (++mark <= sp) {
                I32 proc = SvIVx(*mark);
#ifdef HAS_KILLPG
                if (killpg(proc,val))   /* BSD */
#else
                if (kill(-proc,val))    /* SYSV */
#endif
                    tot--;
            }
        }
        else {
            while (++mark <= sp) {
                if (kill(SvIVx(*mark),val))
                    tot--;
            }
        }
        break;
#endif
    case OP_UNLINK:
        TAINT_PROPER("unlink");
        tot = sp - mark;
        while (++mark <= sp) {
            s = SvPVx(*mark, na);
            if (euid || unsafe) {
                if (UNLINK(s))
                    tot--;
            }
            else {      /* don't let root wipe out directories without -U */
#ifdef HAS_LSTAT
                if (lstat(s,&statbuf) < 0 || S_ISDIR(statbuf.st_mode))
#else
                if (Stat(s,&statbuf) < 0 || S_ISDIR(statbuf.st_mode))
#endif
                    tot--;
                else {
                    if (UNLINK(s))
                        tot--;
                }
            }
        }
        break;
#ifdef HAS_UTIME
    case OP_UTIME:
        TAINT_PROPER("utime");
        if (sp - mark > 2) {
#if defined(I_UTIME) || defined(VMS)
            struct utimbuf utbuf;
#else
            struct {
                long    actime;
                long    modtime;
            } utbuf;
#endif

            Zero(&utbuf, sizeof utbuf, char);
#ifdef BIG_TIME
            utbuf.actime = (Time_t)SvNVx(*++mark);    /* time accessed */
            utbuf.modtime = (Time_t)SvNVx(*++mark);    /* time modified */
#else
            utbuf.actime = SvIVx(*++mark);    /* time accessed */
            utbuf.modtime = SvIVx(*++mark);    /* time modified */
#endif
            tot = sp - mark;
            while (++mark <= sp) {
                if (utime(SvPVx(*mark, na),&utbuf))
                    tot--;
            }
        }
        else
            tot = 0;
        break;
#endif
    }
    return tot;
}

/* Do the permissions allow some operation?  Assumes statcache already set. */
#ifndef VMS /* VMS' cando is in vms.c */
I32
cando(bit, effective, statbufp)
I32 bit;
I32 effective;
register struct stat *statbufp;
{
#ifdef DOSISH
    /* [Comments and code from Len Reed]
     * MS-DOS "user" is similar to UNIX's "superuser," but can't write
     * to write-protected files.  The execute permission bit is set
     * by the Miscrosoft C library stat() function for the following:
     *          .exe files
     *          .com files
     *          .bat files
     *          directories
     * All files and directories are readable.
     * Directories and special files, e.g. "CON", cannot be
     * write-protected.
     * [Comment by Tom Dinger -- a directory can have the write-protect
     *          bit set in the file system, but DOS permits changes to
     *          the directory anyway.  In addition, all bets are off
     *          here for networked software, such as Novell and
     *          Sun's PC-NFS.]
     */

     /* Atari stat() does pretty much the same thing. we set x_bit_set_in_stat
      * too so it will actually look into the files for magic numbers
      */
     return (bit & statbufp->st_mode) ? TRUE : FALSE;

#else /* ! DOSISH */
    if ((effective ? euid : uid) == 0) {        /* root is special */
        if (bit == S_IXUSR) {
            if (statbufp->st_mode & 0111 || S_ISDIR(statbufp->st_mode))
                return TRUE;
        }
        else
            return TRUE;                /* root reads and writes anything */
        return FALSE;
    }
    if (statbufp->st_uid == (effective ? euid : uid) ) {
        if (statbufp->st_mode & bit)
            return TRUE;        /* ok as "user" */
    }
    else if (ingroup((I32)statbufp->st_gid,effective)) {
        if (statbufp->st_mode & bit >> 3)
            return TRUE;        /* ok as "group" */
    }
    else if (statbufp->st_mode & bit >> 6)
        return TRUE;    /* ok as "other" */
    return FALSE;
#endif /* ! DOSISH */
}
#endif /* ! VMS */

I32
ingroup(testgid,effective)
I32 testgid;
I32 effective;
{
    if (testgid == (effective ? egid : gid))
        return TRUE;
#ifdef HAS_GETGROUPS
#ifndef NGROUPS
#define NGROUPS 32
#endif
    {
        Groups_t gary[NGROUPS];
        I32 anum;

        anum = getgroups(NGROUPS,gary);
        while (--anum >= 0)
            if (gary[anum] == testgid)
                return TRUE;
    }
#endif
    return FALSE;
}

#if defined(HAS_MSG) || defined(HAS_SEM) || defined(HAS_SHM)

I32
do_ipcget(optype, mark, sp)
I32 optype;
SV **mark;
SV **sp;
{
    key_t key;
    I32 n, flags;

    key = (key_t)SvNVx(*++mark);
    n = (optype == OP_MSGGET) ? 0 : SvIVx(*++mark);
    flags = SvIVx(*++mark);
    SETERRNO(0,0);
    switch (optype)
    {
#ifdef HAS_MSG
    case OP_MSGGET:
        return msgget(key, flags);
#endif
#ifdef HAS_SEM
    case OP_SEMGET:
        return semget(key, n, flags);
#endif
#ifdef HAS_SHM
    case OP_SHMGET:
        return shmget(key, n, flags);
#endif
#if !defined(HAS_MSG) || !defined(HAS_SEM) || !defined(HAS_SHM)
    default:
        croak("%s not implemented", op_desc[optype]);
#endif
    }
    return -1;                  /* should never happen */
}

I32
do_ipcctl(optype, mark, sp)
I32 optype;
SV **mark;
SV **sp;
{
    SV *astr;
    char *a;
    I32 id, n, cmd, infosize, getinfo;
    I32 ret = -1;
#ifdef __linux__        /* XXX Need metaconfig test */
    union semun unsemds;
#endif

    id = SvIVx(*++mark);
    n = (optype == OP_SEMCTL) ? SvIVx(*++mark) : 0;
    cmd = SvIVx(*++mark);
    astr = *++mark;
    infosize = 0;
    getinfo = (cmd == IPC_STAT);

    switch (optype)
    {
#ifdef HAS_MSG
    case OP_MSGCTL:
        if (cmd == IPC_STAT || cmd == IPC_SET)
            infosize = sizeof(struct msqid_ds);
        break;
#endif
#ifdef HAS_SHM
    case OP_SHMCTL:
        if (cmd == IPC_STAT || cmd == IPC_SET)
            infosize = sizeof(struct shmid_ds);
        break;
#endif
#ifdef HAS_SEM
    case OP_SEMCTL:
        if (cmd == IPC_STAT || cmd == IPC_SET)
            infosize = sizeof(struct semid_ds);
        else if (cmd == GETALL || cmd == SETALL)
        {
            struct semid_ds semds;
#ifdef __linux__        /* XXX Need metaconfig test */
/* linux (and Solaris2?) uses :
   int semctl (int semid, int semnum, int cmd, union semun arg)
       union semun {
            int val;
            struct semid_ds *buf;
            ushort *array;
       };
*/
            union semun semun;
            semun.buf = &semds;
            if (semctl(id, 0, IPC_STAT, semun) == -1)
#else
            if (semctl(id, 0, IPC_STAT, &semds) == -1)
#endif
                return -1;
            getinfo = (cmd == GETALL);
            infosize = semds.sem_nsems * sizeof(short);
                /* "short" is technically wrong but much more portable
                   than guessing about u_?short(_t)? */
        }
        break;
#endif
#if !defined(HAS_MSG) || !defined(HAS_SEM) || !defined(HAS_SHM)
    default:
        croak("%s not implemented", op_desc[optype]);
#endif
    }

    if (infosize)
    {
        STRLEN len;
        if (getinfo)
        {
            SvPV_force(astr, len);
            a = SvGROW(astr, infosize+1);
        }
        else
        {
            a = SvPV(astr, len);
            if (len != infosize)
                croak("Bad arg length for %s, is %lu, should be %ld",
                        op_desc[optype], (unsigned long)len, (long)infosize);
        }
    }
    else
    {
        IV i = SvIV(astr);
        a = (char *)i;          /* ouch */
    }
    SETERRNO(0,0);
    switch (optype)
    {
#ifdef HAS_MSG
    case OP_MSGCTL:
        ret = msgctl(id, cmd, (struct msqid_ds *)a);
        break;
#endif
#ifdef HAS_SEM
    case OP_SEMCTL:
#ifdef __linux__        /* XXX Need metaconfig test */
        unsemds.buf = (struct semid_ds *)a;
        ret = semctl(id, n, cmd, unsemds);
#else
        ret = semctl(id, n, cmd, (struct semid_ds *)a);
#endif
        break;
#endif
#ifdef HAS_SHM
    case OP_SHMCTL:
        ret = shmctl(id, cmd, (struct shmid_ds *)a);
        break;
#endif
    }
    if (getinfo && ret >= 0) {
        SvCUR_set(astr, infosize);
        *SvEND(astr) = '\0';
        SvSETMAGIC(astr);
    }
    return ret;
}

I32
do_msgsnd(mark, sp)
SV **mark;
SV **sp;
{
#ifdef HAS_MSG
    SV *mstr;
    char *mbuf;
    I32 id, msize, flags;
    STRLEN len;

    id = SvIVx(*++mark);
    mstr = *++mark;
    flags = SvIVx(*++mark);
    mbuf = SvPV(mstr, len);
    if ((msize = len - sizeof(long)) < 0)
        croak("Arg too short for msgsnd");
    SETERRNO(0,0);
    return msgsnd(id, (struct msgbuf *)mbuf, msize, flags);
#else
    croak("msgsnd not implemented");
#endif
}

I32
do_msgrcv(mark, sp)
SV **mark;
SV **sp;
{
#ifdef HAS_MSG
    SV *mstr;
    char *mbuf;
    long mtype;
    I32 id, msize, flags, ret;
    STRLEN len;

    id = SvIVx(*++mark);
    mstr = *++mark;
    msize = SvIVx(*++mark);
    mtype = (long)SvIVx(*++mark);
    flags = SvIVx(*++mark);
    if (SvTHINKFIRST(mstr)) {
        if (SvREADONLY(mstr))
            croak("Can't msgrcv to readonly var");
        if (SvROK(mstr))
            sv_unref(mstr);
    }
    SvPV_force(mstr, len);
    mbuf = SvGROW(mstr, sizeof(long)+msize+1);
    
    SETERRNO(0,0);
    ret = msgrcv(id, (struct msgbuf *)mbuf, msize, mtype, flags);
    if (ret >= 0) {
        SvCUR_set(mstr, sizeof(long)+ret);
        *SvEND(mstr) = '\0';
    }
    return ret;
#else
    croak("msgrcv not implemented");
#endif
}

I32
do_semop(mark, sp)
SV **mark;
SV **sp;
{
#ifdef HAS_SEM
    SV *opstr;
    char *opbuf;
    I32 id;
    STRLEN opsize;

    id = SvIVx(*++mark);
    opstr = *++mark;
    opbuf = SvPV(opstr, opsize);
    if (opsize < sizeof(struct sembuf)
        || (opsize % sizeof(struct sembuf)) != 0) {
        SETERRNO(EINVAL,LIB$_INVARG);
        return -1;
    }
    SETERRNO(0,0);
    return semop(id, (struct sembuf *)opbuf, opsize/sizeof(struct sembuf));
#else
    croak("semop not implemented");
#endif
}

I32
do_shmio(optype, mark, sp)
I32 optype;
SV **mark;
SV **sp;
{
#ifdef HAS_SHM
    SV *mstr;
    char *mbuf, *shm;
    I32 id, mpos, msize;
    STRLEN len;
    struct shmid_ds shmds;

    id = SvIVx(*++mark);
    mstr = *++mark;
    mpos = SvIVx(*++mark);
    msize = SvIVx(*++mark);
    SETERRNO(0,0);
    if (shmctl(id, IPC_STAT, &shmds) == -1)
        return -1;
    if (mpos < 0 || msize < 0 || mpos + msize > shmds.shm_segsz) {
        SETERRNO(EFAULT,SS$_ACCVIO);            /* can't do as caller requested */
        return -1;
    }
    shm = (Shmat_t)shmat(id, (char*)NULL, (optype == OP_SHMREAD) ? SHM_RDONLY : 0);
    if (shm == (char *)-1)      /* I hate System V IPC, I really do */
        return -1;
    if (optype == OP_SHMREAD) {
        SvPV_force(mstr, len);
        mbuf = SvGROW(mstr, msize+1);

        Copy(shm + mpos, mbuf, msize, char);
        SvCUR_set(mstr, msize);
        *SvEND(mstr) = '\0';
        SvSETMAGIC(mstr);
    }
    else {
        I32 n;

        mbuf = SvPV(mstr, len);
        if ((n = len) > msize)
            n = msize;
        Copy(mbuf, shm + mpos, n, char);
        if (n < msize)
            memzero(shm + mpos + n, msize - n);
    }
    return shmdt(shm);
#else
    croak("shm I/O not implemented");
#endif
}

#endif /* SYSV IPC */