Python Fax - Send a fax with a large file

Download the Python samples fax API zip file.
Download the Modified OSA files.

This is a more advanced Python code sample to show how to send a fax with a large document. This code sample is based on the Python library for InterFAX available on Github.

This sample demonstrates how to upload a large file to InterFAX using the Document component and then sending a fax to a single recipient while referencing that previously uploaded file - all you need to do in order to change it is to provide a different fax number and a different path to the files that you would like to send. You can also change the size of the chunk that you will be uploading the file with.

     import os

# create a new InterFAX Document
document = interfax.documents.create(

# read the file to send
with open("test.pdf", "rb") as fp:
    cursor = 0
    while True:
        chunk =
        if not chunk:
        next_cursor = cursor + len(chunk)
        # upload each chunk
        document.upload(cursor, next_cursor-1, chunk)
        cursor = next_cursor

# send the fax
  # a valid fax number
  # the document URI


You can check on the status of this fax by following this sample code.

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