"file" command yields "ASCII text, with no line terminators", unless I first edit the file in vim

Question

I am experimenting a strange behaviour which I don't know how to solve. I will explain the scenario:

• From a Python script I'm getting a json from a simple application hosted on parse.
• Once I get the text, I get a sentence from it and save it to a local "txt" file saving it as iso-8859-15.
• Finally I send it to a text to speech processor, which expects receiving it on ISO-8859-15

The weird thing is that once the python script runs, if I run

file my_file.txt

The output is:

my_file.txt: ASCII text, with no line terminators

But if I open my_file.txt with vim, then remove the last "dot" of the sentence, write it again, and save the file: if I do again:

file my_file.txt

now the output is:

my_file.txt: ASCII text

Which solves some problems when processing the voice synthesizer. So, how can I force this behaviour automatically without doing the vim stuff? I have also done many tries with iconv with no success.

Any help would be much appreciated

Edit:

i@raspberrypi ~/main $ hexdump -C my_file.txt

00000000  73 61 6d 70 6c 65 20 61  6e 73 77 65 72 2e 2e     |sample answer..|
0000000f

pi@raspberrypi ~/main $ file my_file.txt
my_file.txt: ASCII text, with no line terminators
pi@raspberrypi ~/main $ vim my_file.txt
pi@raspberrypi ~/main $ file my_file.txt
my_file.txt: ASCII text
pi@raspberrypi ~/main $ hexdump -C my_file.txt

00000000  73 61 6d 70 6c 65 20 61  6e 73 77 65 72 2e 2e 0a  |sample answer...|
00000010

Sample file

Python code:

import json,httplib
from random import randint
import codecs

connection = httplib.HTTPSConnection('api.parse.com', 443)
connection.connect()
connection.request('GET', '/1/classes/XXXX', '', {
       "X-Parse-Application-Id": "xxxx",
       "X-Parse-REST-API-Key": "xxxx"
     })
result = json.loads(connection.getresponse().read())

pos = randint(0,len(result['results'])-1)
sentence = result['results'][pos]['sentence'].encode('iso-8859-15')
response = result['results'][pos]['response'].encode('iso-8859-15')

text_file = codecs.open("sentence.txt", "w","ISO-8859-15")
text_file.write("%s" % sentence)
text_file.close()

text_file = open("response.txt","w")
text_file.write("%s" % response)
text_file.close()

Answer 1

The standard /bin/echo can be used to add that newline to the end of the file for you:

$ echo -n 'ssss'>test
$ file test
test: ASCII text, with no line terminators
$ hexdump -C test 
00000000  73 73 73 73                                       |ssss|
00000004
$ echo >> test
$ file test
test: ASCII text
$ hexdump -C test 
00000000  73 73 73 73 0a                                    |ssss.|
00000005
$ 

Another option would be to add it in your Python code:

text_file = open("response.txt","w")
text_file.write("%s" % response)
text_file.write("\n")  # <-- newline added here
text_file.close()

Answer 2

The simplest solution is to append the newline in the write command:

text_file.write("%s\n" % sentence)

My sample program to demonstrate

import codecs
sentence = 'something'
text_file = codecs.open("sentence.txt", "w","ISO-8859-15")
text_file.write("%s" % sentence)
text_file.close()
text_file = codecs.open("sentence2.txt", "w","ISO-8859-15")
text_file.write("%s\n" % sentence)
text_file.close()

And the result:

$ file sentence.txt 
sentence.txt: ASCII text, with no line terminators
$ file sentence2.txt 
sentence2.txt: ASCII text

The explanation is that the variable you are writing does not contain the newline and write() writes exactly hat you give it.