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File: libc.info,  Node: Deleting Files,  Next: Renaming Files,  Prev: Symbolic Links,  Up: File System Interface
14.6 Deleting Files
===================
You can delete a file with 'unlink' or 'remove'.
   Deletion actually deletes a file name.  If this is the file's only
name, then the file is deleted as well.  If the file has other remaining
names (*note Hard Links::), it remains accessible under those names.
 -- Function: int unlink (const char *FILENAME)
     Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
     Concepts::.
     The 'unlink' function deletes the file name FILENAME.  If this is a
     file's sole name, the file itself is also deleted.  (Actually, if
     any process has the file open when this happens, deletion is
     postponed until all processes have closed the file.)
     The function 'unlink' is declared in the header file 'unistd.h'.
     This function returns '0' on successful completion, and '-1' on
     error.  In addition to the usual file name errors (*note File Name
     Errors::), the following 'errno' error conditions are defined for
     this function:
     'EACCES'
          Write permission is denied for the directory from which the
          file is to be removed, or the directory has the sticky bit set
          and you do not own the file.
     'EBUSY'
          This error indicates that the file is being used by the system
          in such a way that it can't be unlinked.  For example, you
          might see this error if the file name specifies the root
          directory or a mount point for a file system.
     'ENOENT'
          The file name to be deleted doesn't exist.
     'EPERM'
          On some systems 'unlink' cannot be used to delete the name of
          a directory, or at least can only be used this way by a
          privileged user.  To avoid such problems, use 'rmdir' to
          delete directories.  (On GNU/Linux and GNU/Hurd systems
          'unlink' can never delete the name of a directory.)
     'EROFS'
          The directory containing the file name to be deleted is on a
          read-only file system and can't be modified.
 -- Function: int rmdir (const char *FILENAME)
     Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
     Concepts::.
     The 'rmdir' function deletes a directory.  The directory must be
     empty before it can be removed; in other words, it can only contain
     entries for '.' and '..'.
     In most other respects, 'rmdir' behaves like 'unlink'.  There are
     two additional 'errno' error conditions defined for 'rmdir':
     'ENOTEMPTY'
     'EEXIST'
          The directory to be deleted is not empty.
     These two error codes are synonymous; some systems use one, and
     some use the other.  GNU/Linux and GNU/Hurd systems always use
     'ENOTEMPTY'.
     The prototype for this function is declared in the header file
     'unistd.h'.
 -- Function: int remove (const char *FILENAME)
     Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
     Concepts::.
     This is the ISO C function to remove a file.  It works like
     'unlink' for files and like 'rmdir' for directories.  'remove' is
     declared in 'stdio.h'.