chroot.2

来自「<B>Digital的Unix操作系统VAX 4.2源码</B>」· 2 代码 · 共 76 行

.\" SCCSID: @(#)chroot.2	8.3	3/29/91
.\" Last modified by Michaud 16-Sept-1986 1000.
.TH chroot 2
.SH Name
chroot \- change root directory
.SH Syntax
.nf
chroot(\fIdirname\fP)
char *\fIdirname;\fP
.fi
.SH Description
.NXR "chroot system call"
.NXA "chdir system call" "chroot system call"
.NXR "root directory" "changing"
The
.I dirname
is the address of the pathname of a directory,
terminated by a null byte.
The
.PN chroot
system call causes this directory
to become the root directory (/).
.PP
For a directory to become the root directory,
a process must have execute (search) access to the directory.
.PP
This call is restricted to the superuser.
.SH Return Values
Upon successful completion, a value of 0 is returned.  Otherwise,
a value of \-1 is returned and \fIerrno\fP is set to indicate an error.
.SH Diagnostics
The
.PN chroot
system call fails and the root directory is unchanged under the
following conditions:
.TP 15
[ENOTDIR]
A component of the \fIdirname\fP is not a directory.
.TP 15
[ENAMETOOLONG]
A component of a \fIdirname\fP exceeded 255 characters, or
an entire \fIdirname\fP exceeded 1023 characters.
.TP 15
[ENOENT]
The \fIdirname\fP argument points to the name of a directory which
does not exist, or to an empty string and the environment
defined is POSIX or SYSTEM_FIVE.
.TP 15
[EFAULT]
The
.I dirname 
points outside the process's allocated address space.
.TP 15
[ELOOP]
Too many symbolic links were encountered in translating
the pathname.
.TP 15
[EIO]
An I/O error occurred while reading from or writing to the
file system.
.TP 15
[ESTALE]
The file handle given in the argument is invalid.  The file 
referred to by that file handle no longer exists or has
been revoked.
.TP
[ETIMEDOUT]
A connect request or remote file operation failed because the connected party
did not properly respond after a period of time that is dependent on
the communications protocol.
.TP 15
[EPERM]
The effective user ID is not that of superuser.
.SH See Also
chdir(2)