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unlink(2)                   BSD System Calls Manual                  unlink(2)


NAME

     unlink -- remove directory entry


SYNOPSIS

     #include <unistd.h>

     int
     unlink(const char *path);


DESCRIPTION

     The unlink() function removes the link named by path from its directory
     and decrements the link count of the file which was referenced by the
     link.  If that decrement reduces the link count of the file to zero, and
     no process has the file open, then all resources associated with the file
     are reclaimed.  If one or more process have the file open when the last
     link is removed, the link is removed, but the removal of the file is
     delayed until all references to it have been closed.


RETURN VALUES

     Upon successful completion, a value of 0 is returned.  Otherwise, a value
     of -1 is returned and errno is set to indicate the error.


ERRORS

     The unlink() system call will fail if:

     [EACCES]           Search permission is denied for a component of the
                        path prefix.

     [EACCES]           Write permission is denied on the directory containing
                        the link to be removed.

     [EBUSY]            The entry to be unlinked is the mount point for a
                        mounted file system.

     [EBUSY]            The file named by the path argument cannot be unlinked
                        because it is being used by the system or by another
                        process.

     [EFAULT]           Path points outside the process's allocated address
                        space.

     [EIO]              An I/O error occurs while deleting the directory entry
                        or deallocating the inode.

     [ELOOP]            Too many symbolic links are encountered in translating
                        the pathname.  This is taken to be indicative of a
                        looping symbolic link.

     [ENAMETOOLONG]     A component of a pathname exceeds {NAME_MAX} charac-
                        ters, or an entire path name exceeds {PATH_MAX} char-
                        acters (possibly as a result of expanding a symlink).

     [ENOENT]           The named file does not exist.

     [ENOTDIR]          A component of the path prefix is not a directory.

     [EPERM]            The named file is a directory and the effective user
                        ID of the process is not the super-user.

     [EPERM]            The directory containing the file is marked sticky,
                        and neither the containing directory nor the file to
                        be removed are owned by the effective user ID.

     [EROFS]            The named file resides on a read-only file system.


SEE ALSO

     close(2), link(2), rmdir(2), symlink(7)


HISTORY

     An unlink() function call appeared in Version 6 AT&T UNIX.

4th Berkeley Distribution        June 4, 1993        4th Berkeley Distribution

Mac OS X 10.9.1 - Generated Mon Jan 6 18:35:10 CST 2014