|HP-UX Reference > C
HP-UX 11i Version 3: February 2007
chown(), fchown(), lchown() — change owner and group of a file
int chown(const char *path, uid_t owner, gid_t group);
int lchown(const char *path, uid_t owner, gid_t group);
int fchown(int fildes, uid_t owner, gid_t group);
The chown() system call changes the user and group ownership of a file. path points to the path name of a file. chown() sets the owner ID and group ID of the file to the numeric values contained in owner and group respectively. A value of UID_NO_CHANGE or GID_NO_CHANGE can be specified in owner or group to leave unchanged the file's owner ID or group ID, respectively. Note that owner and group should be less than UID_MAX (see limits(5)).
The group ownership of a file can be changed to any group in the current process's access list or to the real or effective group ID of the current process. If privilege groups are supported and the user has the CHOWN privilege, the file can be given to any group.
If the path given to chown() contains a symbolic link as the last element, this link is traversed and path name resolution continues. chown() changes the owner and group of the symbolic link's target, rather than the owner and group of the link.
The fchown() system call functions exactly like chown(), except that it operates on a file descriptor instead of a path name. fildes is a file descriptor.
The lchown() system call sets the owner ID and group ID of the named file just as chown() does, except in the case where the named file is a symbolic link. In this case, lchown() changes the owner and group of the symbolic link file itself.
Access Control Lists - HFS File Systems Only
A user can allow or deny specific individuals and groups access to a file by using the file's access control list (see acl(5)). When using chown() in conjunction with HFS ACLs, if the new owner and/or group does not have an optional ACL entry corresponding to user.% and/or %.group in the file's access control list, the file's access permission bits remain unchanged. However, if the new owner and/or group is already designated by an optional ACL entry of user.% and/or %.group, chown() sets the file's permission bits (and the three basic ACL entries) to the permissions contained in that entry.
Access Control Lists - JFS File Systems Only
A user can allow or deny specific individuals and groups access to a file by using the file's access control list (see aclv(5)). When using chown() in conjunction with JFS ACLs, if the new owner and/or group of a file have optional ACL entries corresponding to user:uid:perm and/or group:gid:perm in the file's access control list, those entries remain in the ACL but no longer have any effect, being superseded by the file's user::perm and/or group::perm entries.
Only processes with an effective user ID equal to the file owner or a user with the OWNER privilege can change the ownership of a file. If privilege groups are supported, the owner of a file can change the ownership only as a member of a privilege group allowing CHOWN, as set up by the setprivgrp command (see setprivgrp(1M)). All users get the CHOWN privilege by default.
When a process changes the ownership or group of a file, the file system may clear the set-user-ID and set-group-ID bits.
See privileges(5) for more information about privileged access on systems that support fine-grained privileges.
chown() and fchown() return the following values:
If chown() or lchown() fails, errno is set to one of the following values:
If fchown() fails, errno is set to one of the following values:
chown() was developed by AT&T.
fchown() was developed by the University of California, Berkeley.