1CHROOT(2)                  Linux Programmer's Manual                 CHROOT(2)
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NAME

6       chroot - change root directory
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SYNOPSIS

9       #include <unistd.h>
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11       int chroot(const char *path);
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DESCRIPTION

14       chroot()  changes  the  root  directory  of the calling process to that
15       specified in path.  This directory will be used for pathnames beginning
16       with /.  The root directory is inherited by all children of the calling
17       process.
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19       Only a privileged process (Linux: one with the CAP_SYS_CHROOT  capabil‐
20       ity) may call chroot().
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22       This  call changes an ingredient in the pathname resolution process and
23       does nothing else.
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25       This call does not change the current working directory, so that  after
26       the call '.' can be outside the tree rooted at '/'.  In particular, the
27       superuser can escape from a "chroot jail" by doing:
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29           mkdir foo; chroot foo; cd ..
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31       This call does not close open file descriptors, and such file  descrip‐
32       tors may allow access to files outside the chroot tree.
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RETURN VALUE

35       On  success,  zero is returned.  On error, -1 is returned, and errno is
36       set appropriately.
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ERRORS

39       Depending on the file system, other errors can be returned.   The  more
40       general errors are listed below:
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42       EACCES Search  permission  is denied on a component of the path prefix.
43              (See also path_resolution(7).)
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45       EFAULT path points outside your accessible address space.
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47       EIO    An I/O error occurred.
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49       ELOOP  Too many symbolic links were encountered in resolving path.
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51       ENAMETOOLONG
52              path is too long.
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54       ENOENT The file does not exist.
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56       ENOMEM Insufficient kernel memory was available.
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58       ENOTDIR
59              A component of path is not a directory.
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61       EPERM  The caller has insufficient privilege.
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CONFORMING TO

64       SVr4, 4.4BSD, SUSv2 (marked LEGACY).  This  function  is  not  part  of
65       POSIX.1-2001.
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NOTES

68       A  child  process created via fork(2) inherits its parent's root direc‐
69       tory.  The root directory is left unchanged by execve(2).
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71       FreeBSD has a stronger jail() system call.
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SEE ALSO

74       chdir(2), path_resolution(7)
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COLOPHON

77       This page is part of release 3.22 of the Linux  man-pages  project.   A
78       description  of  the project, and information about reporting bugs, can
79       be found at http://www.kernel.org/doc/man-pages/.
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83Linux                             2008-06-23                         CHROOT(2)
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