cpython/Modules/posixmodule.c

/***********************************************************
Copyright 1991, 1992, 1993, 1994 by Stichting Mathematisch Centrum,
Amsterdam, The Netherlands.

                        All Rights Reserved

Permission to use, copy, modify, and distribute this software and its 
documentation for any purpose and without fee is hereby granted, 
provided that the above copyright notice appear in all copies and that
both that copyright notice and this permission notice appear in 
supporting documentation, and that the names of Stichting Mathematisch
Centrum or CWI not be used in advertising or publicity pertaining to
distribution of the software without specific, written prior permission.

STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO
THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE
FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

******************************************************************/

/* POSIX module implementation */

#ifdef _M_IX86
#define NT
/* NT may be defined externally as well.  If it is defined, the module is
   actually called 'nt', not 'posix', and some functions don't exist. */
#endif

#include "allobjects.h"
#include "modsupport.h"
#include "ceval.h"

#include <string.h>
#include <errno.h>

#ifndef macintosh
#include <sys/types.h>
#include <sys/stat.h>
#endif 

#include "mytime.h"		/* For clock_t on some systems */

#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#else /* !HAVE_UNISTD_H */

#ifdef macintosh
#include "macdefs.h"
#else
extern int mkdir PROTO((const char *, mode_t));
extern int chdir PROTO((const char *));
extern int rmdir PROTO((const char *));
extern int chmod PROTO((const char *, mode_t));
extern int chown PROTO((const char *, uid_t, gid_t));
extern char *getcwd PROTO((char *, int));
extern char *strerror PROTO((int));
extern int link PROTO((const char *, const char *));
extern int rename PROTO((const char *, const char *));
extern int stat PROTO((const char *, struct stat *));
extern int unlink PROTO((const char *));
extern int pclose PROTO((FILE *));
#ifdef HAVE_SYMLINK
extern int symlink PROTO((const char *, const char *));
#endif
#ifdef HAVE_LSTAT
extern int lstat PROTO((const char *, struct stat *));
#endif
#endif /* macintosh */
#endif /* !HAVE_UNISTD_H */

#if 1
/* XXX These are for SunOS4.1.3 but shouldn't hurt elsewhere */
extern int rename();
extern int pclose();
extern int lstat();
extern int symlink();
#endif

#ifdef HAVE_UTIME_H
#include <utime.h>
#endif

#ifdef HAVE_SYS_TIMES_H
#include <sys/times.h>
#endif

#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif

#ifdef HAVE_SYS_UTSNAME_H
#include <sys/utsname.h>
#endif

#ifndef MAXPATHLEN
#define MAXPATHLEN 1024
#endif

/* unistd.h defines _POSIX_VERSION on POSIX.1 systems.  */
#if defined(DIRENT) || defined(_POSIX_VERSION)
#include <dirent.h>
#define NLENGTH(dirent) (strlen((dirent)->d_name))
#else /* not (DIRENT or _POSIX_VERSION) */
#define dirent direct
#define NLENGTH(dirent) ((dirent)->d_namlen)
#ifdef SYSNDIR
#include <sys/ndir.h>
#endif /* SYSNDIR */
#ifdef SYSDIR
#include <sys/dir.h>
#endif /* SYSDIR */
#ifdef NDIR
#include <ndir.h>
#endif /* NDIR */
#endif /* not (DIRENT or _POSIX_VERSION) */

#ifdef NT
#include <direct.h>
#include <io.h>
#include <process.h>
#include <windows.h>
#define popen   _popen
#endif /* NT */

#ifdef OS2
#include <io.h>
#endif

/* Return a dictionary corresponding to the POSIX environment table */

extern char **environ;

static object *
convertenviron()
{
	object *d;
	char **e;
	d = newdictobject();
	if (d == NULL)
		return NULL;
	if (environ == NULL)
		return d;
	/* XXX This part ignores errors */
	for (e = environ; *e != NULL; e++) {
		object *v;
		char *p = strchr(*e, '=');
		if (p == NULL)
			continue;
		v = newstringobject(p+1);
		if (v == NULL)
			continue;
		*p = '\0';
		(void) dictinsert(d, *e, v);
		*p = '=';
		DECREF(v);
	}
	return d;
}


static object *PosixError; /* Exception posix.error */

/* Set a POSIX-specific error from errno, and return NULL */

static object * posix_error() { 	return err_errno(PosixError);
}


/* POSIX generic methods */

static object *
posix_1str(args, func)
	object *args;
	int (*func) FPROTO((const char *));
{
	char *path1;
	int res;
	if (!getargs(args, "s", &path1))
		return NULL;
	BGN_SAVE
	res = (*func)(path1);
	END_SAVE
	if (res < 0)
		return posix_error();
	INCREF(None);
	return None;
}

static object *
posix_2str(args, func)
	object *args;
	int (*func) FPROTO((const char *, const char *));
{
	char *path1, *path2;
	int res;
	if (!getargs(args, "(ss)", &path1, &path2))
		return NULL;
	BGN_SAVE
	res = (*func)(path1, path2);
	END_SAVE
	if (res < 0)
		return posix_error();
	INCREF(None);
	return None;
}

static object *
posix_strint(args, func)
	object *args;
	int (*func) FPROTO((const char *, int));
{
	char *path;
	int i;
	int res;
	if (!getargs(args, "(si)", &path, &i))
		return NULL;
	BGN_SAVE
	res = (*func)(path, i);
	END_SAVE
	if (res < 0)
		return posix_error();
	INCREF(None);
	return None;
}

static object *
posix_strintint(args, func)
	object *args;
	int (*func) FPROTO((const char *, int, int));
{
	char *path;
	int i,i2;
	int res;
	if (!getargs(args, "(sii)", &path, &i, &i2))
		return NULL;
	BGN_SAVE
	res = (*func)(path, i, i2);
	END_SAVE
	if (res < 0)
		return posix_error();
	INCREF(None);
	return None;
}

static object *
posix_do_stat(self, args, statfunc)
	object *self;
	object *args;
	int (*statfunc) FPROTO((const char *, struct stat *));
{
	struct stat st;
	char *path;
	int res;
	if (!getargs(args, "s", &path))
		return NULL;
	BGN_SAVE
	res = (*statfunc)(path, &st);
	END_SAVE
	if (res != 0)
		return posix_error();
	return mkvalue("(llllllllll)",
		    (long)st.st_mode,
		    (long)st.st_ino,
		    (long)st.st_dev,
		    (long)st.st_nlink,
		    (long)st.st_uid,
		    (long)st.st_gid,
		    (long)st.st_size,
		    (long)st.st_atime,
		    (long)st.st_mtime,
		    (long)st.st_ctime);
}


/* POSIX methods */

static object *
posix_chdir(self, args)
	object *self;
	object *args;
{
	return posix_1str(args, chdir);
}

static object *
posix_chmod(self, args)
	object *self;
	object *args;
{
	return posix_strint(args, chmod);
}

#ifdef HAVE_CHOWN
static object *
posix_chown(self, args)
	object *self;
	object *args;
{
	return posix_strintint(args, chown);
}
#endif

static object *
posix_getcwd(self, args)
	object *self;
	object *args;
{
	char buf[1026];
	char *res;
	if (!getnoarg(args))
		return NULL;
	BGN_SAVE
	res = getcwd(buf, sizeof buf);
	END_SAVE
	if (res == NULL)
		return posix_error();
	return newstringobject(buf);
}

#ifdef HAVE_LINK
static object *
posix_link(self, args)
	object *self;
	object *args;
{
	return posix_2str(args, link);
}
#endif

#ifdef NT
static object *
posix_listdir(self, args)
	object *self;
	object *args;
{
	char *name;
	int len;
	object *d, *v;
	HANDLE hFindFile;
	WIN32_FIND_DATA FileData;
	char namebuf[MAX_PATH+5];

	if (!getargs(args, "s#", &name, &len))
		return NULL;
	if (len >= MAX_PATH) {
		err_setstr(ValueError, "path too long");
		return NULL;
	}
	strcpy(namebuf, name);
	if (namebuf[len-1] != '/' && namebuf[len-1] != '\\')
		namebuf[len++] = '/';
	strcpy(namebuf + len, "*.*");

	if ((d = newlistobject(0)) == NULL)
		return NULL;

	hFindFile = FindFirstFile(namebuf, &FileData);
	if (hFindFile == INVALID_HANDLE_VALUE) {
		errno = GetLastError();
		return posix_error();
	}
	do {
		v = newstringobject(FileData.cFileName);
		if (v == NULL) {
			DECREF(d);
			d = NULL;
			break;
		}
		if (addlistitem(d, v) != 0) {
			DECREF(v);
			DECREF(d);
			d = NULL;
			break;
		}
		DECREF(v);
	} while (FindNextFile(hFindFile, &FileData) == TRUE);

	if (FindClose(hFindFile) == FALSE) {
		errno = GetLastError();
		return posix_error();
	}

	return d;
}
#else /* ! NT */
static object *
posix_listdir(self, args)
	object *self;
	object *args;
{
	char *name;
	object *d, *v;
	DIR *dirp;
	struct dirent *ep;
	if (!getargs(args, "s", &name))
		return NULL;
	BGN_SAVE
	if ((dirp = opendir(name)) == NULL) {
		RET_SAVE
		return posix_error();
	}
	if ((d = newlistobject(0)) == NULL) {
		closedir(dirp);
		RET_SAVE
		return NULL;
	}
	while ((ep = readdir(dirp)) != NULL) {
		v = newstringobject(ep->d_name);
		if (v == NULL) {
			DECREF(d);
			d = NULL;
			break;
		}
		if (addlistitem(d, v) != 0) {
			DECREF(v);
			DECREF(d);
			d = NULL;
			break;
		}
		DECREF(v);
	}
	closedir(dirp);
	END_SAVE

	return d;
}
#endif /* ! NT */

static object *
posix_mkdir(self, args)
	object *self;
	object *args;
{
	return posix_strint(args, mkdir);
}

#ifdef HAVE_NICE
static object *
posix_nice(self, args)
	object *self;
	object *args;
{
	int increment, value;

	if (!getargs(args, "i", &increment))
		return NULL;
	value = nice(increment);
	if (value == -1)
		return posix_error();
	return newintobject((long) value);
}
#endif /* HAVE_NICE */

static object *
posix_rename(self, args)
	object *self;
	object *args;
{
	return posix_2str(args, rename);
}

static object *
posix_rmdir(self, args)
	object *self;
	object *args;
{
	return posix_1str(args, rmdir);
}

static object *
posix_stat(self, args)
	object *self;
	object *args;
{
	return posix_do_stat(self, args, stat);
}

static object *
posix_system(self, args)
	object *self;
	object *args;
{
	char *command;
	long sts;
	if (!getargs(args, "s", &command))
		return NULL;
	BGN_SAVE
	sts = system(command);
	END_SAVE
	return newintobject(sts);
}

static object *
posix_umask(self, args)
	object *self;
	object *args;
{
	int i;
	if (!getintarg(args, &i))
		return NULL;
	i = umask(i);
	if (i < 0)
		return posix_error();
	return newintobject((long)i);
}

static object *
posix_unlink(self, args)
	object *self;
	object *args;
{
	return posix_1str(args, unlink);
}

#ifdef HAVE_UNAME
static object *
posix_uname(self, args)
	object *self;
	object *args;
{
	struct utsname u;
	object *v;
	int res;
	if (!getnoarg(args))
		return NULL;
	BGN_SAVE
	res = uname(&u);
	END_SAVE
	if (res < 0)
		return posix_error();
	return mkvalue("(sssss)",
		       u.sysname,
		       u.nodename,
		       u.release,
		       u.version,
		       u.machine);
}
#endif /* HAVE_UNAME */

static object *
posix_utime(self, args)
	object *self;
	object *args;
{
	char *path;
	int res;

#ifdef HAVE_UTIME_H
	struct utimbuf buf;
#define ATIME buf.actime
#define MTIME buf.modtime
#define UTIME_ARG &buf
#else
	time_t buf[2];
#define ATIME buf[0]
#define MTIME buf[1]
#define UTIME_ARG buf
#endif

	if (!getargs(args, "(s(ll))", &path, &ATIME, &MTIME))
		return NULL;
	BGN_SAVE
	res = utime(path, UTIME_ARG);
	END_SAVE
	if (res < 0)
		return posix_error();
	INCREF(None);
	return None;
#undef UTIME_ARG
#undef ATIME
#undef MTIME
}


/* Process operations */

static object *
posix__exit(self, args)
	object *self;
	object *args;
{
	int sts;
	if (!getintarg(args, &sts))
		return NULL;
	_exit(sts);
	/* NOTREACHED */
}

static object *
posix_execv(self, args)
	object *self;
	object *args;
{
	char *path;
	object *argv;
	char **argvlist;
	int i, argc;
	object *(*getitem) PROTO((object *, int));

	/* execv has two arguments: (path, argv), where
	   argv is a list or tuple of strings. */

	if (!getargs(args, "(sO)", &path, &argv))
		return NULL;
	if (is_listobject(argv)) {
		argc = getlistsize(argv);
		getitem = getlistitem;
	}
	else if (is_tupleobject(argv)) {
		argc = gettuplesize(argv);
		getitem = gettupleitem;
	}
	else {
 badarg:
		err_badarg();
		return NULL;
	}

	argvlist = NEW(char *, argc+1);
	if (argvlist == NULL)
		return NULL;
	for (i = 0; i < argc; i++) {
		if (!getargs((*getitem)(argv, i), "s", &argvlist[i])) {
			DEL(argvlist);
			goto badarg;
		}
	}
	argvlist[argc] = NULL;

#ifdef BAD_EXEC_PROTOTYPES
	execv(path, (const char **) argvlist);
#else
	execv(path, argvlist);
#endif

	/* If we get here it's definitely an error */

	DEL(argvlist);
	return posix_error();
}

static object *
posix_execve(self, args)
	object *self;
	object *args;
{
	char *path;
	object *argv, *env;
	char **argvlist;
	char **envlist;
	object *key, *val;
	int i, pos, argc, envc;
	object *(*getitem) PROTO((object *, int));

	/* execve has three arguments: (path, argv, env), where
	   argv is a list or tuple of strings and env is a dictionary
	   like posix.environ. */

	if (!getargs(args, "(sOO)", &path, &argv, &env))
		return NULL;
	if (is_listobject(argv)) {
		argc = getlistsize(argv);
		getitem = getlistitem;
	}
	else if (is_tupleobject(argv)) {
		argc = gettuplesize(argv);
		getitem = gettupleitem;
	}
	else {
		err_setstr(TypeError, "argv must be tuple or list");
		return NULL;
	}
	if (!is_dictobject(env)) {
		err_setstr(TypeError, "env must be dictionary");
		return NULL;
	}

	argvlist = NEW(char *, argc+1);
	if (argvlist == NULL) {
		err_nomem();
		return NULL;
	}
	for (i = 0; i < argc; i++) {
		if (!getargs((*getitem)(argv, i),
			     "s;argv must be list of strings",
			     &argvlist[i])) {
			goto fail_1;
		}
	}
	argvlist[argc] = NULL;

	i = getmappingsize(env);
	envlist = NEW(char *, i + 1);
	if (envlist == NULL) {
		err_nomem();
		goto fail_1;
	}
	pos = 0;
	envc = 0;
	while (mappinggetnext(env, &pos, &key, &val)) {
		char *p, *k, *v;
		if (!getargs(key, "s;non-string key in env", &k) ||
		    !getargs(val, "s;non-string value in env", &v)) {
			goto fail_2;
		}
		p = NEW(char, getstringsize(key) + getstringsize(val) + 2);
		if (p == NULL) {
			err_nomem();
			goto fail_2;
		}
		sprintf(p, "%s=%s", k, v);
		envlist[envc++] = p;
	}
	envlist[envc] = 0;


#ifdef BAD_EXEC_PROTOTYPES
	execve(path, (const char **)argvlist, envlist);
#else
	execve(path, argvlist, envlist);
#endif
	
	/* If we get here it's definitely an error */

	(void) posix_error();

 fail_2:
	while (--envc >= 0)
		DEL(envlist[envc]);
	DEL(envlist);
 fail_1:
	DEL(argvlist);

	return NULL;
}

static object *
posix_fork(self, args)
	object *self;
	object *args;
{
	int pid;
	if (!getnoarg(args))
		return NULL;
	pid = fork();
	if (pid == -1)
		return posix_error();
	return newintobject((long)pid);
}

static object *
posix_getegid(self, args)
	object *self;
	object *args;
{
	if (!getnoarg(args))
		return NULL;
	return newintobject((long)getegid());
}

static object *
posix_geteuid(self, args)
	object *self;
	object *args;
{
	if (!getnoarg(args))
		return NULL;
	return newintobject((long)geteuid());
}

static object *
posix_getgid(self, args)
	object *self;
	object *args;
{
	if (!getnoarg(args))
		return NULL;
	return newintobject((long)getgid());
}

static object *
posix_getpid(self, args)
	object *self;
	object *args;
{
	if (!getnoarg(args))
		return NULL;
	return newintobject((long)getpid());
}

#ifdef HAVE_GETPGRP
static object *
posix_getpgrp(self, args)
	object *self;
	object *args;
{
	if (!getnoarg(args))
		return NULL;
#ifdef GETPGRP_HAVE_ARG
	return newintobject((long)getpgrp(0));
#else
	return newintobject((long)getpgrp());
#endif
}
#endif /* HAVE_GETPGRP */

#ifdef HAVE_SETPGRP
static object *
posix_setpgrp(self, args)
	object *self;
	object *args;
{
	if (!getnoarg(args))
		return NULL;
#ifdef GETPGRP_HAVE_ARG
	if (setpgrp(0, 0) < 0)
#else
	if (setpgrp() < 0)
#endif
		return posix_error();
	INCREF(None);
	return None;
}

#endif /* HAVE_SETPGRP */

static object *
posix_getppid(self, args)
	object *self;
	object *args;
{
	if (!getnoarg(args))
		return NULL;
	return newintobject((long)getppid());
}

static object *
posix_getuid(self, args)
	object *self;
	object *args;
{
	if (!getnoarg(args))
		return NULL;
	return newintobject((long)getuid());
}

static object *
posix_kill(self, args)
	object *self;
	object *args;
{
	int pid, sig;
	if (!getargs(args, "(ii)", &pid, &sig))
		return NULL;
	if (kill(pid, sig) == -1)
		return posix_error();
	INCREF(None);
	return None;
}

static object *
posix_popen(self, args)
	object *self;
	object *args;
{
	char *name, *mode;
	FILE *fp;
	if (!getargs(args, "(ss)", &name, &mode))
		return NULL;
	BGN_SAVE
	fp = popen(name, mode);
	END_SAVE
	if (fp == NULL)
		return posix_error();
	return newopenfileobject(fp, name, mode, pclose);
}

#ifdef HAVE_SETUID
static object *
posix_setuid(self, args)
	object *self;
	object *args;
{
	int uid;
	if (!getargs(args, "i", &uid))
		return NULL;
	if (setuid(uid) < 0)
		return posix_error();
	INCREF(None);
	return None;
}
#endif

#ifdef HAVE_SETGID
static object *
posix_setgid(self, args)
	object *self;
	object *args;
{
	int gid;
	if (!getargs(args, "i", &gid))
		return NULL;
	if (setgid(gid) < 0)
		return posix_error();
	INCREF(None);
	return None;
}
#endif

#ifdef HAVE_WAITPID
static object *
posix_waitpid(self, args)
	object *self;
	object *args;
{
	int pid, options, sts;
	if (!getargs(args, "(ii)", &pid, &options))
		return NULL;
	BGN_SAVE
	pid = waitpid(pid, &sts, options);
	END_SAVE
	if (pid == -1)
		return posix_error();
	else
		return mkvalue("ii", pid, sts);
}
#endif /* HAVE_WAITPID */

static object *
posix_wait(self, args)
	object *self;
	object *args;
{
	int pid, sts;
	BGN_SAVE
	pid = wait(&sts);
	END_SAVE
	if (pid == -1)
		return posix_error();
	else
		return mkvalue("ii", pid, sts);
}

static object *
posix_lstat(self, args)
	object *self;
	object *args;
{
#ifdef HAVE_LSTAT
	return posix_do_stat(self, args, lstat);
#else /* !HAVE_LSTAT */
	return posix_do_stat(self, args, stat);
#endif /* !HAVE_LSTAT */
}

#ifdef HAVE_READLINK
static object *
posix_readlink(self, args)
	object *self;
	object *args;
{
	char buf[MAXPATHLEN];
	char *path;
	int n;
	if (!getargs(args, "s", &path))
		return NULL;
	BGN_SAVE
	n = readlink(path, buf, (int) sizeof buf);
	END_SAVE
	if (n < 0)
		return posix_error();
	return newsizedstringobject(buf, n);
}
#endif /* HAVE_READLINK */

#ifdef HAVE_SYMLINK
static object *
posix_symlink(self, args)
	object *self;
	object *args;
{
	return posix_2str(args, symlink);
}
#endif /* HAVE_SYMLINK */

#ifdef HAVE_TIMES
#ifndef HZ
#define HZ 60 /* Universal constant :-) */
#endif
static object *
posix_times(self, args)
	object *self;
	object *args;
{
	struct tms t;
	clock_t c;
	if (!getnoarg(args))
		return NULL;
	errno = 0;
	c = times(&t);
	if (c == (clock_t) -1)
		return posix_error();
	return mkvalue("dddd",
		       (double)t.tms_utime / HZ,
		       (double)t.tms_stime / HZ,
		       (double)t.tms_cutime / HZ,
		       (double)t.tms_cstime / HZ);
}
#endif /* HAVE_TIMES */

#ifdef HAVE_SETSID
static object *
posix_setsid(self, args)
	object *self;
	object *args;
{
	if (!getnoarg(args))
		return NULL;
	if (setsid() < 0)
		return posix_error();
	INCREF(None);
	return None;
}
#endif /* HAVE_SETSID */

#ifdef HAVE_SETPGID
static object *
posix_setpgid(self, args)
	object *self;
	object *args;
{
	int pid, pgrp;
	if (!getargs(args, "(ii)", &pid, &pgrp))
		return NULL;
	if (setpgid(pid, pgrp) < 0)
		return posix_error();
	INCREF(None);
	return None;
}
#endif /* HAVE_SETPGID */

#ifdef HAVE_TCGETPGRP
static object *
posix_tcgetpgrp(self, args)
	object *self;
	object *args;
{
	int fd, pgid;
	if (!getargs(args, "i", &fd))
		return NULL;
	pgid = tcgetpgrp(fd);
	if (pgid < 0)
		return posix_error();
	return newintobject((long)pgid);
}
#endif /* HAVE_TCGETPGRP */

#ifdef HAVE_TCSETPGRP
static object *
posix_tcsetpgrp(self, args)
	object *self;
	object *args;
{
	int fd, pgid;
	if (!getargs(args, "(ii)", &fd, &pgid))
		return NULL;
	if (tcsetpgrp(fd, pgid) < 0)
		return posix_error();
       INCREF(None);
	return None;
}
#endif /* HAVE_TCSETPGRP */

/* Functions acting on file descriptors */

static object *
posix_open(self, args)
	object *self;
	object *args;
{
	char *file;
	int flag;
	int mode = 0777;
	int fd;
	if (!getargs(args, "(si)", &file, &flag)) {
		err_clear();
		if (!getargs(args, "(sii)", &file, &flag, &mode))
			return NULL;
	}
	BGN_SAVE
	fd = open(file, flag, mode);
	END_SAVE
	if (fd < 0)
		return posix_error();
	return newintobject((long)fd);
}

static object *
posix_close(self, args)
	object *self;
	object *args;
{
	int fd, res;
	if (!getargs(args, "i", &fd))
		return NULL;
	BGN_SAVE
	res = close(fd);
	END_SAVE
	if (res < 0)
		return posix_error();
	INCREF(None);
	return None;
}

static object *
posix_dup(self, args)
	object *self;
	object *args;
{
	int fd;
	if (!getargs(args, "i", &fd))
		return NULL;
	BGN_SAVE
	fd = dup(fd);
	END_SAVE
	if (fd < 0)
		return posix_error();
	return newintobject((long)fd);
}

static object *
posix_dup2(self, args)
	object *self;
	object *args;
{
	int fd, fd2, res;
	if (!getargs(args, "(ii)", &fd, &fd2))
		return NULL;
	BGN_SAVE
	res = dup2(fd, fd2);
	END_SAVE
	if (res < 0)
		return posix_error();
	INCREF(None);
	return None;
}

static object *
posix_lseek(self, args)
	object *self;
	object *args;
{
	int fd, how;
	long pos, res;
	if (!getargs(args, "(ili)", &fd, &pos, &how))
		return NULL;
#ifdef SEEK_SET
	/* Turn 0, 1, 2 into SEEK_{SET,CUR,END} */
	switch (how) {
	case 0: how = SEEK_SET; break;
	case 1: how = SEEK_CUR; break;
	case 2: how = SEEK_END; break;
	}
#endif
	BGN_SAVE
	res = lseek(fd, pos, how);
	END_SAVE
	if (res < 0)
		return posix_error();
	return newintobject(res);
}

static object *
posix_read(self, args)
	object *self;
	object *args;
{
	int fd, size;
	object *buffer;
	if (!getargs(args, "(ii)", &fd, &size))
		return NULL;
	buffer = newsizedstringobject((char *)NULL, size);
	if (buffer == NULL)
		return NULL;
	BGN_SAVE
	size = read(fd, getstringvalue(buffer), size);
	END_SAVE
	if (size < 0) {
		DECREF(buffer);
		return posix_error();
	}
	resizestring(&buffer, size);
	return buffer;
}

static object *
posix_write(self, args)
	object *self;
	object *args;
{
	int fd, size;
	char *buffer;
	if (!getargs(args, "(is#)", &fd, &buffer, &size))
		return NULL;
	BGN_SAVE
	size = write(fd, buffer, size);
	END_SAVE
	if (size < 0)
		return posix_error();
	return newintobject((long)size);
}

static object *
posix_fstat(self, args)
	object *self;
	object *args;
{
	int fd;
	struct stat st;
	int res;
	if (!getargs(args, "i", &fd))
		return NULL;
	BGN_SAVE
	res = fstat(fd, &st);
	END_SAVE
	if (res != 0)
		return posix_error();
	return mkvalue("(llllllllll)",
		    (long)st.st_mode,
		    (long)st.st_ino,
		    (long)st.st_dev,
		    (long)st.st_nlink,
		    (long)st.st_uid,
		    (long)st.st_gid,
		    (long)st.st_size,
		    (long)st.st_atime,
		    (long)st.st_mtime,
		    (long)st.st_ctime);
}

static object *
posix_fdopen(self, args)
	object *self;
	object *args;
{
	extern int fclose PROTO((FILE *));
	int fd;
	char *mode;
	FILE *fp;
	if (!getargs(args, "(is)", &fd, &mode))
		return NULL;
	BGN_SAVE
	fp = fdopen(fd, mode);
	END_SAVE
	if (fp == NULL)
		return posix_error();
	/* From now on, ignore SIGPIPE and let the error checking
	   do the work. */
	return newopenfileobject(fp, "(fdopen)", mode, fclose);
}

static object *
posix_pipe(self, args)
	object *self;
	object *args;
{
	int fds[2];
	int res;
	if (!getargs(args, ""))
		return NULL;
	BGN_SAVE
	res = pipe(fds);
	END_SAVE
	if (res != 0)
		return posix_error();
	return mkvalue("(ii)", fds[0], fds[1]);
}

static struct methodlist posix_methods[] = {
	{"chdir",	posix_chdir},
	{"chmod",	posix_chmod},
#ifdef HAVE_CHOWN
	{"chown",	posix_chown},
#endif
	{"getcwd",	posix_getcwd},
#ifdef HAVE_LINK
	{"link",	posix_link},
#endif 
	{"listdir",	posix_listdir},
	{"lstat",	posix_lstat},
	{"mkdir",	posix_mkdir},
#ifdef HAVE_NICE
	{"nice",	posix_nice},
#endif
#ifdef HAVE_READLINK
	{"readlink",	posix_readlink},
#endif
	{"rename",	posix_rename},
	{"rmdir",	posix_rmdir},
	{"stat",	posix_stat},
#ifdef HAVE_SYMLINK
	{"symlink",	posix_symlink},
#endif
	{"system",	posix_system},
	{"umask",	posix_umask},
#ifdef HAVE_UNAME
	{"uname",	posix_uname},
#endif
	{"unlink",	posix_unlink},
#ifndef NT
	{"utime",	posix_utime},
#endif /* ! NT */
#ifdef HAVE_TIMES
	{"times",	posix_times},
#endif
	{"_exit",	posix__exit},
	{"execv",	posix_execv},
	{"execve",	posix_execve},
#ifndef NT
	{"fork",	posix_fork},
	{"getegid",	posix_getegid},
	{"geteuid",	posix_geteuid},
	{"getgid",	posix_getgid},
#endif /* ! NT */
	{"getpid",	posix_getpid},
#ifdef HAVE_GETPGRP
	{"getpgrp",	posix_getpgrp},
#endif
#ifndef NT
	{"getppid",	posix_getppid},
	{"getuid",	posix_getuid},
	{"kill",	posix_kill},
#endif /* ! NT */
	{"popen",	posix_popen},
#ifdef HAVE_SETUID
	{"setuid",	posix_setuid},
#endif
#ifdef HAVE_SETGID
	{"setgid",	posix_setgid},
#endif
#ifdef HAVE_SETPGRP
	{"setpgrp",	posix_setpgrp},
#endif
#ifndef NT
	{"wait",	posix_wait},
#endif /* ! NT */
#ifdef HAVE_WAITPID
	{"waitpid",	posix_waitpid},
#endif
#ifdef HAVE_SETSID
	{"setsid",	posix_setsid},
#endif
#ifdef HAVE_SETPGID
	{"setpgid",	posix_setpgid},
#endif
#ifdef HAVE_TCGETPGRP
	{"tcgetpgrp",	posix_tcgetpgrp},
#endif
#ifdef HAVE_TCSETPGRP
	{"tcsetpgrp",	posix_tcsetpgrp},
#endif
	{"open",	posix_open},
	{"close",	posix_close},
	{"dup",		posix_dup},
	{"dup2",	posix_dup2},
	{"lseek",	posix_lseek},
	{"read",	posix_read},
	{"write",	posix_write},
	{"fstat",	posix_fstat},
	{"fdopen",	posix_fdopen},
#ifndef NT
	{"pipe",	posix_pipe},
#endif /* ! NT */

	{NULL,		NULL}		 /* Sentinel */
};


#ifdef NT
void
initnt()
{
	object *m, *d, *v;
	
	m = initmodule("nt", posix_methods);
	d = getmoduledict(m);
	
	/* Initialize nt.environ dictionary */
	v = convertenviron();
	if (v == NULL || dictinsert(d, "environ", v) != 0)
		fatal("can't define nt.environ");
	DECREF(v);
	
	/* Initialize nt.error exception */
	PosixError = newstringobject("nt.error");
	if (PosixError == NULL || dictinsert(d, "error", PosixError) != 0)
		fatal("can't define nt.error");
}
#else /* ! NT */
void
initposix()
{
	object *m, *d, *v;
	
	m = initmodule("posix", posix_methods);
	d = getmoduledict(m);
	
	/* Initialize posix.environ dictionary */
	v = convertenviron();
	if (v == NULL || dictinsert(d, "environ", v) != 0)
		fatal("can't define posix.environ");
	DECREF(v);
	
	/* Initialize posix.error exception */
	PosixError = newstringobject("posix.error");
	if (PosixError == NULL || dictinsert(d, "error", PosixError) != 0)
		fatal("can't define posix.error");
}
#endif /* ! NT */