xref: /dragonfly/lib/libc/sys/unlink.2 (revision f9a239ec)
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32.\"     @(#)unlink.2	8.1 (Berkeley) 6/4/93
33.\" $FreeBSD: src/lib/libc/sys/unlink.2,v 1.8.2.4 2001/12/14 18:34:02 ru Exp $
34.\" $DragonFly: src/lib/libc/sys/unlink.2,v 1.3 2005/02/03 02:43:44 drhodus Exp $
35.\"
36.Dd June 4, 1993
37.Dt UNLINK 2
38.Os
39.Sh NAME
40.Nm unlink
41.Nd remove directory entry
42.Sh LIBRARY
43.Lb libc
44.Sh SYNOPSIS
45.In unistd.h
46.Ft int
47.Fn unlink "const char *path"
48.Sh DESCRIPTION
49The
50.Fn unlink
51function
52removes the link named by
53.Fa path
54from its directory and decrements the link count of the
55file which was referenced by the link.
56If that decrement reduces the link count of the file
57to zero,
58and no process has the file open, then
59all resources associated with the file are reclaimed.
60If one or more process have the file open when the last link is removed,
61the link is removed, but the removal of the file is delayed until
62all references to it have been closed.
63.Fa path
64may not be a directory.
65.Sh RETURN VALUES
66.Rv -std unlink
67.Sh ERRORS
68The
69.Fn unlink
70succeeds unless:
71.Bl -tag -width Er
72.It Bq Er ENOTDIR
73A component of the path prefix is not a directory.
74.It Bq Er ENAMETOOLONG
75A component of a pathname exceeded 255 characters,
76or an entire path name exceeded 1023 characters.
77.It Bq Er ENOENT
78The named file does not exist.
79.It Bq Er EACCES
80Search permission is denied for a component of the path prefix.
81.It Bq Er EACCES
82Write permission is denied on the directory containing the link
83to be removed.
84.It Bq Er ELOOP
85Too many symbolic links were encountered in translating the pathname.
86.It Bq Er EPERM
87The named file has its immutable or append-only flag set (see chflags(2)).
88.It Bq Er EPERM
89The named file is a directory.
90.It Bq Er EPERM
91The directory containing the file is marked sticky,
92and neither the containing directory nor the file to be removed
93are owned by the effective user ID.
94.It Bq Er EBUSY
95The entry to be unlinked is the mount point for a
96mounted file system.
97.It Bq Er EIO
98An I/O error occurred while deleting the directory entry
99or deallocating the inode.
100.It Bq Er EROFS
101The named file resides on a read-only file system.
102.It Bq Er EFAULT
103.Fa Path
104points outside the process's allocated address space.
105.El
106.Sh SEE ALSO
107.Xr close 2 ,
108.Xr link 2 ,
109.Xr rmdir 2 ,
110.Xr symlink 7
111.Sh HISTORY
112An
113.Fn unlink
114function call appeared in
115.At v6 .
116.Pp
117The
118.Fn unlink
119system call traditionally allows the super-user to unlink directories which
120can damage the filesystem integrity.  This implementation no longer permits
121it.
122