bsd/man/man2/unlink.2

   1 .\"     $NetBSD: unlink.2,v 1.7 1995/02/27 12:39:13 cgd Exp $
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  34 .\"     @(#)unlink.2    8.1 (Berkeley) 6/4/93
  35 .\"
  36 .Dd June 4, 1993
  37 .Dt UNLINK 2
  38 .Os BSD 4
  39 .Sh NAME
  40 .Nm unlink
  41 .Nd remove directory entry
  42 .Sh SYNOPSIS
  43 .Fd #include <unistd.h>
  44 .Ft int
  45 .Fo unlink
  46 .Fa "const char *path"
  47 .Fc
  48 .Sh DESCRIPTION
  49 The
  50 .Fn unlink
  51 function
  52 removes the link named by
  53 .Fa path
  54 from its directory and decrements the link count of the
  55 file which was referenced by the link.
  56 If that decrement reduces the link count of the file
  57 to zero,
  58 and no process has the file open, then
  59 all resources associated with the file are reclaimed.
  60 If one or more process have the file open when the last link is removed,
  61 the link is removed, but the removal of the file is delayed until
  62 all references to it have been closed.
  63 .Sh RETURN VALUES
  64 Upon successful completion, a value of 0 is returned.
  65 Otherwise, a value of -1 is returned and
  66 .Va errno
  67 is set to indicate the error.
  68 .Sh ERRORS
  69 The
  70 .Fn unlink
  71 system call will fail if:
  72 .Bl -tag -width Er
  73 .\" ===========
  74 .It Bq Er EACCES
  75 Search permission is denied for a component of the path prefix.
  76 .\" ===========
  77 .It Bq Er EACCES
  78 Write permission is denied on the directory containing the link
  79 to be removed.
  80 .\" ===========
  81 .It Bq Er EBUSY
  82 The entry to be unlinked is the mount point for a
  83 mounted file system.
  84 .\" ===========
  85 .It Bq Er EBUSY
  86 The file named by the
  87 .Fa path
  88 argument cannot be unlinked
  89 because it is being used by the system or by another process.
  90 .\" ===========
  91 .It Bq Er EFAULT
  92 .Fa Path
  93 points outside the process's allocated address space.
  94 .\" ===========
  95 .It Bq Er EIO
  96 An I/O error occurs while deleting the directory entry
  97 or deallocating the inode.
  98 .\" ===========
  99 .It Bq Er ELOOP
 100 Too many symbolic links are encountered in translating the pathname.
 101 This is taken to be indicative of a looping symbolic link.
 102 .\" ===========
 103 .It Bq Er ENAMETOOLONG
 104 A component of a pathname exceeds
 105 .Dv {NAME_MAX}
 106 characters, or an entire path name exceeds
 107 .Dv {PATH_MAX}
 108 characters (possibly as a result of expanding a symlink).
 109 .\" ===========
 110 .It Bq Er ENOENT
 111 The named file does not exist.
 112 .\" ===========
 113 .It Bq Er ENOTDIR
 114 A component of the path prefix is not a directory.
 115 .\" ===========
 116 .It Bq Er EPERM
 117 The named file is a directory and the effective user ID
 118 of the process is not the super-user.
 119 .\" ===========
 120 .It Bq Er EPERM
 121 The directory containing the file is marked sticky,
 122 and neither the containing directory nor the file to be removed
 123 are owned by the effective user ID.
 124 .\" ===========
 125 .It Bq Er EROFS
 126 The named file resides on a read-only file system.
 127 .El
 128 .Sh SEE ALSO
 129 .Xr close 2 ,
 130 .Xr link 2 ,
 131 .Xr rmdir 2 ,
 132 .Xr symlink 7
 133 .Sh HISTORY
 134 An
 135 .Fn unlink
 136 function call appeared in
 137 .At v6 .