posixpath.py 文件源码

def dirname(p):
    """Returns the directory component of a pathname"""
    p = os.fspath(p)
    sep = _get_sep(p)
    i = p.rfind(sep) + 1
    head = p[:i]
    if head and head != sep*len(head):
        head = head.rstrip(sep)
    return head


# Is a path a symbolic link?
# This will always return false on systems where os.lstat doesn't exist.