// license that can be found in the LICENSE file.

//go:build darwin || dragonfly || freebsd || (linux && !arm64 && !loong64 && !riscv64) || netbsd || openbsd

package main

import "syscall"

func dup2(oldfd, newfd int) error {
	return syscall.Dup2(oldfd, newfd)

// license that can be found in the LICENSE file.

//go:build (linux && arm64) || (linux && loong64) || (linux && riscv64)

package main

import "syscall"

func dup2(oldfd, newfd int) error {
	return syscall.Dup3(oldfd, newfd, 0)

// function creates a pipe and Dups the read end to a known number
// that the C code can also use.

const (
	fd = 30
)

func init() {
	var p [2]int
	if e := syscall.Pipe(p[0:]); e != nil {
		fmt.Fprintf(os.Stderr, "pipe: %v\n", e)
		os.Exit(2)
	}

	if e := dup2(p[0], fd); e != nil {
		fmt.Fprintf(os.Stderr, "dup2: %v\n", e)
		os.Exit(2)
	}

	const str = "PASS"

//go:cgo_import_dynamic abort abort ""
//go:cgo_import_dynamic arc4random_buf arc4random_buf ""
//go:cgo_import_dynamic close close ""
//go:cgo_import_dynamic dlsym dlsym ""
//go:cgo_import_dynamic dup dup ""
//go:cgo_import_dynamic dup2 dup2 ""
//go:cgo_import_dynamic dyld_shared_cache_iterate_text dyld_shared_cache_iterate_text ""
//go:cgo_import_dynamic execve execve ""
//go:cgo_import_dynamic exit exit ""

//go:cgo_import_dynamic arc4random_buf arc4random_buf ""
//go:cgo_import_dynamic bzero bzero ""
//go:cgo_import_dynamic close close ""
//go:cgo_import_dynamic dlsym dlsym ""
//go:cgo_import_dynamic dup dup ""
//go:cgo_import_dynamic dup2 dup2 ""
//go:cgo_import_dynamic dyld_shared_cache_iterate_text dyld_shared_cache_iterate_text ""
//go:cgo_import_dynamic execve execve ""
//go:cgo_import_dynamic exit exit ""
//go:cgo_import_dynamic fstat fstat ""

//go:build linux && (ppc64 || ppc64le)

package syscall

import (
	"unsafe"
)

const (
	_SYS_setgroups  = SYS_SETGROUPS
	_SYS_clone3     = 435
	_SYS_faccessat2 = 439
	_SYS_fchmodat2  = 452
)

//sys	Dup2(oldfd int, newfd int) (err error)
//sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
//sys	Fchown(fd int, uid int, gid int) (err error)
//sys	Fstat(fd int, stat *Stat_t) (err error)

			}
			if err1 != 0 {
				goto childerror
			}
			fd[i] = nextfd
			nextfd++
		}
	}

	// Pass 2: dup fd[i] down onto i.
	for i = 0; i < len(fd); i++ {
		if fd[i] == -1 {
			RawSyscall(SYS_CLOSE, uintptr(i), 0, 0)
			continue
		}
		if fd[i] == i {
			// dup2(i, i) won't clear close-on-exec flag on Linux,
			// probably not elsewhere either.

package syscall

import (
	"unsafe"
)

const (
	_SYS_setgroups  = SYS_SETGROUPS
	_SYS_clone3     = 435
	_SYS_faccessat2 = 439
	_SYS_fchmodat2  = 452
)

//sys	Dup2(oldfd int, newfd int) (err error)
//sys	Fchown(fd int, uid int, gid int) (err error)
//sys	Fstat(fd int, stat *Stat_t) (err error)
//sys	Fstatfs(fd int, buf *Statfs_t) (err error)
//sys	Ftruncate(fd int, length int64) (err error)

//go:cgo_import_dynamic libc_chdir chdir "libc.a/shr_64.o"
//go:cgo_import_dynamic libc_chroot chroot "libc.a/shr_64.o"
//go:cgo_import_dynamic libc_dup2 dup2 "libc.a/shr_64.o"
//go:cgo_import_dynamic libc_execve execve "libc.a/shr_64.o"
//go:cgo_import_dynamic libc_fcntl fcntl "libc.a/shr_64.o"
//go:cgo_import_dynamic libc_fork fork "libc.a/shr_64.o"

//sys	Chmod(path string, mode uint32) (err error)
//sys	Chown(path string, uid int, gid int) (err error)
//sys	Chroot(path string) (err error)
//sys	Close(fd int) (err error)
//sys	Dup(fd int) (nfd int, err error)
//sys	Dup2(from int, to int) (err error)
//sys	dup3(from int, to int, flags int) (err error)
//sys	Fchdir(fd int) (err error)
//sys	Fchflags(fd int, flags int) (err error)
//sys	Fchmod(fd int, mode uint32) (err error)