Creating empty file python

Python create empty file — Unix

I want to create empty file using Python script in Unix environment. Could see different ways mentioned of achieving the same. What are the benefits/pitfalls of one over the other.

os.system('touch abc') open('abc','a').close() open('abc','a') subprocess.call(['touch','abc']) 

4 Answers 4

Well, for a start, the ones that rely on touch are not portable. They won’t work under standard Windows, for example, without the installation of CygWin, GNUWin32, or some other package providing a touch utility..

They also involve the creation of a separate process for doing the work, something that’s totally unnecessary in this case.

Of the four, I would probably use open(‘abc’,’a’).close() if the intent is to try and just create the file if it doesn’t exist. In my opinion, that makes the intent clear.

But, if you’re trying to create an empty file, I’d probably be using the w write mode rather than the a append mode.

In addition, you probably also want to catch the exception if, for example, you cannot actually create the file.

(or ‘w’ instead of ‘a’ if the intent is to truncate the file if it already exists).

Invoking a separate process to do something Python can do itself is wasteful, and non-portable to platforms where the external command is not available. (Additionally, os.system uses two processes — one more for a shell to parse the command line — and is being deprecated in favor of subprocess .)

Not closing an open filehandle when you’re done with it is bad practice, and could cause resource depletion in a larger program (you run out of filehandles if you open more and more files and never close them).

open() may block if the name corresponds to a named pipe. You could use os.open() to open it in non-blocking mode.

To create an empty file on Unix in Python:

import os try: os.close(os.open('abc', os.O_WRONLY | os.O_CREAT | os.O_EXCL | getattr(os, "O_CLOEXEC", 0) | os.O_NONBLOCK | os.O_NOCTTY)) except OSError: pass # decide what to consider an error in your case and reraise # 1. is it an error if 'abc' entry already exists? # 2. is it an error if 'abc' is a directory or a symlink to a directory? # 3. is it an error if 'abc' is a named pipe? # 4. it is probably an error if the parent directory is not writable # or the filesystem is read-only (can't create a file) 

try: open('abc', 'ab', 0).close() except OSError: pass # see the comment above 

Without the explicit .close() call, non-reference-counting Python implementations such as Pypy, Jython may delay closing the file until garbage collection is run (it may exhaust available file descriptors for your process).

The latter example may stuck on FIFO and follows symlinks. On my system, it is equivalent to:

from os import * open("abc", O_WRONLY|O_CREAT|O_APPEND|O_CLOEXEC, 0666) 

In addition, touch command updates the access and modification times of existing files to the current time.

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How to create an empty file using Python?

Empty describes anything which contains nothing. Using a computer as an example, an empty file is one that has no data in it; it has 0 bytes and is in plain text format having no data kept in a file.

Let us discuss various types of empty files that can be created using python.

Creating an empty CSV file

The plain text file format known as a CSV file (Comma Separated Values file) is used to structure tabular data in a particular way.It can only contain actual text data that is, printable ASCII or Unicode characters—because it is a plain text file.

The structure of a CSV file is revealed by the name itself. Each distinct data value is typically separated in CSV files by a comma. The extension used for CSV file is .csv.

There are various ways to create a blank CSV file in Python. open operator is the simplest approach to create an empty csv file.It is accessible without requiring the import of any other modules. However, Python modules like pandas can also be used to generate CSV files.

Following are the multiple ways to create an empty CSV file −

Creating an empty CSV file using with open

Pass in the name of the new file and ‘w’ as the second parameter to make the file writable in order to create an empty csv file using with open. A new csv file is created if the file name doesn’t already exist.The content will be changed if the file already exists. Pass in «a» to append the content to the file to avoid this happening.

Example

Following is an example to create an empty CSV file with open −

with open('sample.csv', 'w') as creating_new_csv_file: pass print("Empty File Created Successfully") 
 

Output

On executing the above program, an empty csv file is created with the file name ‘sample’.

Empty File Created Successfully

Note − It is advisable to make sure the file doesn’t already exist and, if it does, to append to it rather than overwrite it by using «a» instead of «w.» If in the access mode argument ‘w’ parameter is given, the new material replaces any existing content in the file or leaves empty files vacant.

// Create an empty CSV file with open using 'a': with open('file.csv', 'a') as creating_new_csv_file: passCreating an empty CSV file using pandas

Some Python modules include file creation and file opening methods. It includes the pandas module.Use .to csv() method to produce a blank csv file with pandas.

Example

The pandas module plays a key role in this illustration. Then, based on an empty list, a blank DataFrame is created. Finally, the .to csv() method is used to write the empty DataFrame. The file is generated because it doesn’t already exist. pandas is installed usin the command pip install pandas in command prompt

Following is an example to create an empty CSV file using pandas

# importing the package import pandas as pd # creating new pandas DataFrame dataframe = pd.DataFrame(list()) # writing empty DataFrame to the new csv file dataframe.to_csv('file.csv') print("File Created Successfully") 

Output

On executing, the above program creates an empty csv file, displaying the following message.

Empty File Created Successfully

Creating an empty Text file

The most common sort of file is a text file, which contains text. Rich text formats and plain text can both be found in text files. A straightforward tool like Notepad can be used to create a plain text file by any computer user.

The extension used for text file is .txt

Syntax

Following is the syntax used to create an empty text file:

f = open(path_of_the_file, mode)

The path to the text file you want to generate is specified by the path_of_the_text_file parameter in this syntax. A new text file is created in one of the following modes

• Use «w» to open a file for writing. If the file doesn’t already exist, the open() method is used to create it. If not, the contents of the current file will be replaced.
• Pressing «x» will allow you to open a file for an exclusive creation. If the file is present, the open() function raises an error.

Example

Following code writes some text into a new file called writing.txt:

with open('writing.txt', 'w') as file: pass print("Empty File Created Successfully") 
 

Output

On executing the above program, an empty text file is created displaying the foillowing message

Empty File Created Successfully

Note − Before generating a file in the directory for example−

‘C:\Users\Lenovo\Downloads\writing.txt’, you must make sure that the docs directory already exists. An exception occurs if you don’t.

Following is an example to create an empty text file by providing the path:

with open('D:\writing.txt', 'w') as file: pass 

This will create an empty text file is created with the name of ‘writing’ in D drive.

Creating an empty Excel file

A spreadsheet application is Excel.Excel arranges data in columns and rows, unlike word processors like Microsoft Word. Cells are the places where rows and columns intersects. Each cell is filled with information, such as text, a number, or a formula.

There are several extensions used for excel file such as xlsx for Excel Workbook, .xls for Excel 97- Excel 2003 Workbook and Microsoft Excel 5.0/95 Workbook, .xml for XML Data and XML Spreadsheet etc

Example

Following is an example to create an empty excel file:

# importing the module from openpyxl import Workbook # create a workbook as .xlsx file def create_workbook(path): workbook = Workbook() workbook.save(path) if __name__ == "__main__": create_workbook("file.xlsx") print("File Created Successfully") 

Output

File Created Successfully

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how to create empty file in python [duplicate]

I would like to create an empty file in Python. But I have difficulty creating one..Below is the Python code I used to create but it gives me error:

gdsfile = "/home/hha/temp.gds" if not (os.path.isfile(gdsfile)): os.system(touch gdsfile) 

Error I got: File «/home/hha/bin/test.py», line 29 os.system(touch gdsfile) ^ SyntaxError: invalid syntax But from the command line, I am able to create new file using: touch Thank you very much for your help Howard

The argument to os.system needs to be a string. That’s not what you’re passing right now. Also, there’s no reason to call out to the touch command when you could just use Python’s own open method.

1 Answer 1

First you have a syntax error because os.system() expects a string argument and you have not provided one. This will fix your code:

os.system('touch <>'.format(gdsfile)) 

which constructs a string and passes it to os.system() .

But a better way (in Python >= 3.3) is to simply open the file using the open() builtin:

gdsfile = "/home/hha/temp.gds" try: open(gdsfile, 'x') except FileExistsError: pass 

This specifies mode x which means exclusive creation — the operation will fail if the file already exists, but create it if it does not.

This is safer than using os.path.isfile() followed by open() because it avoids the potential race condition where the file might be created by another process in between the check and the create.

If you are using Python 2, or an earlier version of Python 3, you can use os.open() to open the file with the exclusive flag.

import os import errno gdsfile = "/home/hha/temp.gds" try: os.close(os.open(gdsfile, os.O_CREAT|os.O_EXCL)) except OSError as exc: if exc.errno != errno.EEXIST: raise 

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Python, how to create an empty file

It accepts 2 parameters: the file path, and the mode.

You can use a as the mode, to tell Python to open the file in append mode:

file = '/Users/flavio/test.txt' open(file, 'a').close() #or open(file, mode='a').close()

If the file already exists, its content is not modified. To clear its content, use the w flag instead:

open(file, 'w').close() #or open(file, mode='w').close()

When you open a file, you must remember to close it after you’ve finished working with it. In this case, we close it immediately, as our goal is to create an empty file.

Remember to close the file, otherwise it will remain open until the end of the program, when it will be automatically closed.

Alternatively, you can use with :

This will automatically close the file.

Creating a file can raise an OSError exception, for example if the disk is full, so we use a try block to catch it and gracefully handle the problem by printing an error message:

file = '/Users/flavio/test.txt' try: open(file, 'a').close() except OSError: print('Failed creating the file') else: print('File created')

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