Make directory path

Make directory path is a draft programming task. It is not yet considered ready to be promoted as a complete task, for reasons that should be found in its talk page.

Given a path to a directory (for example ./path/to/dir) create the directory and any missing parents. If the directory already exists, return successfully.

This task is named after the posix mkdir -p command, and several libraries which implement the same behavior. Ideally implementations will work equally well cross-platform (on windows, linux, and OS X).

Python

<lang Python> from errno import EEXIST from os import mkdir, curdir from os.path import split, exists

def mkdirp(path, mode=0777):

   head, tail = split(path)
   if not tail:
       head, tail = split(head)
   if head and tail and not exists(head):
       try:
           mkdirp(head, mode)
       except OSError as e:
           # be happy if someone already created the path
           if e.errno != EEXIST:
               raise
       if tail == curdir:  # xxx/newdir/. exists if xxx/newdir exists
           return
   try:
       mkdir(path, mode)
   except OSError as e:
       # be happy if someone already created the path
       if e.errno != EEXIST:
           raise

</lang>

Above is a modified version of the standard library's os.makedirs, for pedagogical purposes. In practice, you would be more likely to use the standard library call:

<lang Python> def mkdirp(path):

   try:
       os.makedirs(path)
   except OSError as exc: # Python >2.5
       if exc.errno == errno.EEXIST and os.path.isdir(path):
           pass
       else: raise

</lang>

In Python3 this becomes even simpler:

<lang Python> def mkdirp(path):

   os.makedirs(path, exist_ok=True)

</lang>