bsd/man/man2/unlink.2

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  34 .\"     @(#)unlink.2    8.1 (Berkeley) 6/4/93
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  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 .Fn unlink "const char *path"
  46 .Sh DESCRIPTION
  47 The
  48 .Fn unlink
  49 function
  50 removes the link named by
  51 .Fa path
  52 from its directory and decrements the link count of the
  53 file which was referenced by the link.
  54 If that decrement reduces the link count of the file
  55 to zero,
  56 and no process has the file open, then
  57 all resources associated with the file are reclaimed.
  58 If one or more process have the file open when the last link is removed,
  59 the link is removed, but the removal of the file is delayed until
  60 all references to it have been closed.
  61 .Sh RETURN VALUES
  62 Upon successful completion, a value of 0 is returned.
  63 Otherwise, a value of -1 is returned and
  64 .Va errno
  65 is set to indicate the error.
  66 .Sh ERRORS
  67 The
  68 .Fn unlink
  69 succeeds unless:
  70 .Bl -tag -width Er
  71 .It Bq Er ENOTDIR
  72 A component of the path prefix is not a directory.
  73 .It Bq Er ENAMETOOLONG
  74 A component of a pathname exceeded
  75 .Dv {NAME_MAX}
  76 characters, or an entire path name exceeded
  77 .Dv {PATH_MAX}
  78 characters.
  79 .It Bq Er ENOENT
  80 The named file does not exist.
  81 .It Bq Er EACCES
  82 Search permission is denied for a component of the path prefix.
  83 .It Bq Er EACCES
  84 Write permission is denied on the directory containing the link
  85 to be removed.
  86 .It Bq Er ELOOP
  87 Too many symbolic links were encountered in translating the pathname.
  88 .It Bq Er EPERM
  89 The named file is a directory and the effective user ID
  90 of the process is not the super-user.
  91 .It Bq Er EPERM
  92 The directory containing the file is marked sticky,
  93 and neither the containing directory nor the file to be removed
  94 are owned by the effective user ID.
  95 .It Bq Er EBUSY
  96 The entry to be unlinked is the mount point for a
  97 mounted file system.
  98 .It Bq Er EIO
  99 An I/O error occurred while deleting the directory entry
 100 or deallocating the inode.
 101 .It Bq Er EROFS
 102 The named file resides on a read-only file system.
 103 .It Bq Er EFAULT
 104 .Fa Path
 105 points outside the process's allocated address space.
 106 .El
 107 .Sh SEE ALSO
 108 .Xr close 2 ,
 109 .Xr link 2 ,
 110 .Xr rmdir 2
 111 .Xr symlink 7
 112 .Sh HISTORY
 113 An
 114 .Fn unlink
 115 function call appeared in
 116 .At v6 .