In this post I summarize the commonly-used methods in Python os package.
method related to paths#
| method | description |
|---|---|
| os.path.join | join string to from a path |
| os.path.split | split directory and file name |
| os.path.basename | get the base name of file from a complete path |
| os.path.abspath | get the absolute path a file |
| os.path.dirname | get the directory name from a path |
If you want to combine several string to form a valid path, you can use
os.path.join(). For example, if you want to combine "F:\\paper_ref",
"cnn_classify", "hinton2012.bib" into a complete path，you can manually
combine them using path separator of your system. But this way has some
potential portability issue and is also error-prone. The best way is to use
os.path.join method.
os.path.join("F:\\paper_ref","cnn_classify","hinton2012.bib")
os.path.split can split the directory name and file anme, for example,
os.path.split("d:/my_program/read_image.cc")
# output: ('d:/my_program', 'read_image.cc')
you can use os.path.basename to remove directory info and only get the base
name of a file.
os.path.basename("f:/test/test.jpg") # output: 'test.jpg'
With os.path.abspath, we can get the absolute path of a file in a folder.
Suppose there is file named colour_themes.conf under current directory, you
can use following command to get its absolute path,
os.path.abspath('colour_themes.conf')
# output: '/home/jdhao/files/colour_themes.conf'
The os.path.dirname() method will return the path of a file (not including
the file name)
os.path.dirname("file/music/song1.mp3")
# output: file/music
check path or file#
| method | decription |
|---|---|
| os.path.isabs() | decide if a path is absolute path |
| os.path.isdir() | decide if a path is directory path and check if it really exists |
| os.path.isfile() | decide if the given string is a file, also check if it really exists |
| os.path.exists() | check if a file or directory really exists |
directory manipulations#
| method | description |
|---|---|
| os.getcwd() | get current working directory |
| os.chdir() | change current working directory |
| os.listdir() | list sub-directory and files under a certain directory1 |
| os.mkdir() | create a new directory |
| os.rmdir() | remove an empty directory, it can not remove non-empty directory2 |
| os.remove() | delete a file |
some attribute#
There are also several use attribute. For better portability of your code, you should considering using these attribute instead of hard code.
| attribute | description |
|---|---|
| os.linesep | line break character |
| os.sep | separator in a normal directory path name |
| os.pathsep | separator for the PATH environment variable |
References#
note that this method only output sub-directory and file names, with no path info ↩︎
if you want to delete a non-empty directory, use shutil.rmtree ↩︎