1LCHOWN(3P) POSIX Programmer's Manual LCHOWN(3P)
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6 This manual page is part of the POSIX Programmer's Manual. The Linux
7 implementation of this interface may differ (consult the corresponding
8 Linux manual page for details of Linux behavior), or the interface may
9 not be implemented on Linux.
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12 lchown - change the owner and group of a symbolic link
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15 #include <unistd.h>
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17 int lchown(const char *path, uid_t owner, gid_t group);
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21 The lchown() function shall be equivalent to chown(), except in the
22 case where the named file is a symbolic link. In this case, lchown()
23 shall change the ownership of the symbolic link file itself, while
24 chown() changes the ownership of the file or directory to which the
25 symbolic link refers.
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28 Upon successful completion, lchown() shall return 0. Otherwise, it
29 shall return -1 and set errno to indicate an error.
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32 The lchown() function shall fail if:
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34 EACCES Search permission is denied on a component of the path prefix of
35 path.
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37 EINVAL The owner or group ID is not a value supported by the implemen‐
38 tation.
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40 ELOOP A loop exists in symbolic links encountered during resolution of
41 the path argument.
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43 ENAMETOOLONG
44 The length of a pathname exceeds {PATH_MAX} or a pathname compo‐
45 nent is longer than {NAME_MAX}.
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47 ENOENT A component of path does not name an existing file or path is an
48 empty string.
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50 ENOTDIR
51 A component of the path prefix of path is not a directory.
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53 EOPNOTSUPP
54 The path argument names a symbolic link and the implementation
55 does not support setting the owner or group of a symbolic link.
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57 EPERM The effective user ID does not match the owner of the file and
58 the process does not have appropriate privileges.
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60 EROFS The file resides on a read-only file system.
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63 The lchown() function may fail if:
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65 EIO An I/O error occurred while reading or writing to the file sys‐
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68 EINTR A signal was caught during execution of the function.
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70 ELOOP More than {SYMLOOP_MAX} symbolic links were encountered during
71 resolution of the path argument.
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73 ENAMETOOLONG
74 Pathname resolution of a symbolic link produced an intermediate
75 result whose length exceeds {PATH_MAX}.
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78 The following sections are informative.
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81 Changing the Current Owner of a File
82 The following example shows how to change the ownership of the symbolic
83 link named /modules/pass1 to the user ID associated with "jones" and
84 the group ID associated with "cnd".
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86 The numeric value for the user ID is obtained by using the getpwnam()
87 function. The numeric value for the group ID is obtained by using the
88 getgrnam() function.
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91 #include <sys/types.h>
92 #include <unistd.h>
93 #include <pwd.h>
94 #include <grp.h>
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97 struct passwd *pwd;
98 struct group *grp;
99 char *path = "/modules/pass1";
100 ...
101 pwd = getpwnam("jones");
102 grp = getgrnam("cnd");
103 lchown(path, pwd->pw_uid, grp->gr_gid);
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106 On implementations which support symbolic links as directory entries
107 rather than files, lchown() may fail.
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110 None.
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113 None.
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116 chown(), symlink(), the Base Definitions volume of
117 IEEE Std 1003.1-2001, <unistd.h>
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120 Portions of this text are reprinted and reproduced in electronic form
121 from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
122 -- Portable Operating System Interface (POSIX), The Open Group Base
123 Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
124 Electrical and Electronics Engineers, Inc and The Open Group. In the
125 event of any discrepancy between this version and the original IEEE and
126 The Open Group Standard, the original IEEE and The Open Group Standard
127 is the referee document. The original Standard can be obtained online
128 at http://www.opengroup.org/unix/online.html .
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132IEEE/The Open Group 2003 LCHOWN(3P)