Given an absolute path for a file (Unix-style), simplify it. Or in other words, convert it to the canonical path.
In a UNIX-style file system, a period
. refers to the current directory. Furthermore, a double period
.. moves the directory up a level. For more information, see: Absolute path vs relative path in Linux/Unix
Note that the returned canonical path must always begin with a slash
/, and there must be only a single slash
/ between two directory names. The last directory name (if it exists) must not end with a trailing
/. Also, the canonical path must be the shortest string representing the absolute path.