rename

Change the name of a file

View other versions (4)

Contents

Interface
Description
Caveat
Return Values
Errors
See Also
Page Comments

Interface

#include <stdio.h>
int  rename (const char *from, const char *to)

Description

Rename causes the link named from to be renamed as to. If to exists, it is first removed. Both from and to must be of the same type (that is, both directories or both non-directories), and must reside on the same file system.

Rename guarantees that an instance of to will always exist, even if the system should crash in the middle of the operation.

If the final component of from is a symbolic link, the symbolic link is renamed, not the file or directory to which it points.

The following code attempts to rename the file "fred.txt" to "wilma.txt".

Example 1

#include <stdio.h>
 
int main()
{
  rename("fred.txt", "wilma.txt");
  return 0;
}

Caveat

The system can deadlock if a loop in the file system graph is present. This loop takes the form of an entry in directory 'a,' say 'a/foo,' being a hard link to directory 'b,' and an entry in directory 'b,' say 'b/bar,' being a hard link to directory 'a.' When such a loop exists and two separate processes attempt to perform 'rename a/foo b/bar' and 'rename b/bar a/foo', respectively, the system may deadlock attempting to lock both directories for modification. Hard links to directories should be replaced by symbolic links by the system administrator.

Return Values

A 0 value is returned if the operation succeeds, otherwise rename returns -1 and the global variable errno indicates the reason for the failure.

Errors

Rename will fail and neither of the argument files will be affected if: <table cellspacing="0" class="refpage" style="margin-left:25px"> <tr> <td valign="top" nowrap> [ENAMETOOLONG] </td> <td valign="top"> A component of a pathname exceeded {NAME_MAX} characters, or an entire path name exceeded {PATH_MAX} characters. </td> </tr> <tr> <td valign="top" nowrap> [ENOENT] </td> <td valign="top"> A component of the \c from path does not exist, or a path prefix of \c to does not exist. </td> </tr> <tr> <td valign="top" nowrap> [EACCES] </td> <td valign="top"> A component of either path prefix denies search permission. </td> </tr> <tr> <td valign="top" nowrap> [EACCES] </td> <td valign="top"> The requested link requires writing in a directory with a mode that denies write permission. </td> </tr> <tr> <td valign="top" nowrap> [EPERM] </td> <td valign="top"> The directory containing \c from is marked sticky, and neither the containing directory nor \c from are owned by the effective user ID. </td> </tr> <tr> <td valign="top" nowrap> [EPERM] </td> <td valign="top"> The \c to file exists, the directory containing \c to is marked sticky, and neither the containing directory nor \c to are owned by the effective user ID. </td> </tr> <tr> <td valign="top" nowrap> [ELOOP] </td> <td valign="top"> Too many symbolic links were encountered in translating either pathname. </td> </tr> <tr> <td valign="top" nowrap> [ENOTDIR] </td> <td valign="top"> A component of either path prefix is not a directory. </td> </tr> <tr> <td valign="top" nowrap> [ENOTDIR] </td> <td valign="top"> \c from is a directory, but \c to is not a directory. </td> </tr> <tr> <td valign="top" nowrap> [EISDIR] </td> <td valign="top"> \c to is a directory, but \c from is not a directory. </td> </tr> <tr> <td valign="top" nowrap> [EXDEV] </td> <td valign="top"> The link named by \c to and the file named by \c from are on different logical devices (file systems). Note that this error code will not be returned if the implementation permits cross-device links. </td> </tr> <tr> <td valign="top" nowrap> [ENOSPC] </td> <td valign="top"> The directory in which the entry for the new name is being placed cannot be extended because there is no space left on the file system containing the directory. </td> </tr> <tr> <td valign="top" nowrap> [EDQUOT] </td> <td valign="top"> The directory in which the entry for the new name is being placed cannot be extended because the user's quota of disk blocks on the file system containing the directory has been exhausted. </td> </tr> <tr> <td valign="top" nowrap> [EIO] </td> <td valign="top"> An I/O error occurred while making or updating a directory entry. </td> </tr> <tr> <td valign="top" nowrap> [EROFS] </td> <td valign="top"> The requested link requires writing in a directory on a read-only file system. </td> </tr> <tr> <td valign="top" nowrap> [EFAULT] </td> <td valign="top"> Path points outside the process's allocated address space. </td> </tr> <tr> <td valign="top" nowrap> [EINVAL] </td> <td valign="top"> \c From is a parent directory of \c to, or an attempt is made to rename '.' or '..'. </td> </tr> <tr> <td valign="top" nowrap> [ENOTEMPTY] </td> <td valign="top"> \c To is a directory and is not empty. </td> </tr> </table>