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32 .\" @(#)chroot.2 8.1 (Berkeley) 6/4/93
33 .\" $FreeBSD: src/lib/libc/sys/chroot.2,v 1.7.2.8 2002/12/11 14:06:37 ru Exp $
34 .\" $DragonFly: src/lib/libc/sys/chroot.2,v 1.2 2003/06/17 04:26:47 dillon Exp $
41 .Nd change root directory
47 .Fn chroot "const char *dirname"
50 is the address of the pathname of a directory, terminated by an ASCII NUL.
54 to become the root directory,
55 that is, the starting point for path searches of pathnames
59 In order for a directory to become the root directory
60 a process must have execute (search) access for that directory.
62 It should be noted that
64 has no effect on the process's current directory.
66 This call is restricted to the super-user.
68 Depending on the setting of the
69 .Ql kern.chroot_allow_open_directories
70 sysctl variable, open filedescriptors which reference directories
76 .Ql kern.chroot_allow_open_directories
81 if there are any directories open.
84 .Ql kern.chroot_allow_open_directories
85 is set to one (the default),
89 if there are any directories open and the
90 process is already subject to a
95 .Ql kern.chroot_allow_open_directories
96 will bypass the check for open directories
98 Upon successful completion, a value of 0 is returned. Otherwise,
99 a value of -1 is returned and
101 is set to indicate an error.
104 will fail and the root directory will be unchanged if:
107 A component of the path name is not a directory.
109 The effective user ID is not the super-user, or one or more
110 filedescriptors are open directories.
111 .It Bq Er ENAMETOOLONG
112 A component of a pathname exceeded 255 characters,
113 or an entire path name exceeded 1023 characters.
115 The named directory does not exist.
117 Search permission is denied for any component of the path name.
119 Too many symbolic links were encountered in translating the pathname.
122 points outside the process's allocated address space.
124 An I/O error occurred while reading from or writing to the file system.
132 function call appeared in