.\"	$NetBSD: chdir.2,v 1.7 1995/02/27 12:32:00 cgd Exp $
.\"
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.\"     @(#)chdir.2	8.2 (Berkeley) 12/11/93
.\"
.Dd December 11, 1993
.Dt CHDIR 2
.Os BSD 4
.Sh NAME
.Nm chdir ,
.Nm fchdir
.Nd change current working directory
.Sh SYNOPSIS
.Fd #include <unistd.h>
.Ft int
.Fo chdir
.Fa "const char *path"
.Fc
.Ft int
.Fo fchdir
.Fa "int fildes"
.Fc
.Sh DESCRIPTION
The
.Fa path
argument points to the pathname of a directory.
The
.Fn chdir
function
causes the named directory
to become the current working directory, that is,
the starting point for path searches of pathnames not beginning with
a slash,
.Ql / .
.Pp
The
.Fn fchdir
function
causes the directory referenced by
.Fa fildes
to become the current working directory,
the starting point for path searches of pathnames not beginning with
a slash,
.Ql / .
.Pp
In order for a directory to become the current directory,
a process must have execute (search) access to the directory.
.Sh RETURN VALUES
Upon successful completion, a value of 0 is returned.
Otherwise, a value of -1 is returned and
.Va errno
is set to indicate
the error.
.Sh ERRORS
The
.Fn Chdir
system call will fail
and the current working directory will be unchanged
if one or more of the following are true:
.Bl -tag -width Er
.\" ==========
.It Bq Er EACCES
Search permission is denied for any component of
the path name.
.\" ==========
.It Bq Er EFAULT
.Fa Path
points outside the process's allocated address space.
.\" ==========
.It Bq Er EIO
An I/O error occurred while reading from or writing to the file system.
.\" ==========
.It Bq Er ELOOP
Too many symbolic links were encountered in translating the pathname.
This is taken to be indicative of a looping symbolic link.
.\" ==========
.It Bq Er ENAMETOOLONG
A component of a pathname exceeded 
.Dv {NAME_MAX}
characters, or an entire path name exceeded 
.Dv {PATH_MAX}
characters.
.\" ==========
.It Bq Er ENOENT
The named directory does not exist.
.\" ==========
.It Bq Er ENOTDIR
A component of the path prefix is not a directory.
.El
.Pp
.Fn Fchdir
will fail and the current working directory will be unchanged if
one or more of the following are true:
.Bl -tag -width Er
.\" ==========
.It Bq Er EACCES
Search permission is denied for the directory referenced by the
file descriptor.
.\" ==========
.It Bq Er EBADF
The argument
.Fa fildes
is not a valid file descriptor.
.\" ==========
.It Bq Er EINTR
.Fn Fchdir
was interrupted by a signal.
.\" ==========
.It Bq Er EIO
An I/O error occurred while reading from or writing to the file system.
.\" ==========
.It Bq Er ENOTDIR
The file descriptor does not reference a directory.
.El
.Sh SEE ALSO
.Xr chroot 2
.Sh STANDARDS
The 
.Fn chdir
is expected to conform to 
.St -p1003.1-88 .
.Sh HISTORY
The
.Fn fchdir
function call
appeared in
.Bx 4.2 .