python - flask running in mod_wsgi cannot write to /tmp -

apache v2.4.12-2

mod_wsgi v4.4.8-1

python v3.4.2

python-flask v0.10.1-5

arch linux - kernel 3.12.36

i'm using mod_wsgi , flask host server. able reproduce issue following simplified code , generic .wsgi script:

mainserver.py:

import flask  app = flask.flask(__name__)  @app.before_first_request def initstuff():     test_file = '/tmp/test'     open(test_file, 'w') f:         f.write('test')  @app.route('/', methods=['get']) def rootdir():     return 'hello world' 

mainserver.wsgi:

from mainserver import app application 

expected: file contents 'test' written in /tmp

actual outcome: no file written. no errors reported in log

if run same code instead point other directory user has permission write, creates file expected. /tmp directory having issue.

if run above code directly , use flask's built in server (app.run), can create file in /tmp expected without issues.

i've ensured mod_wsgi server running same user script app.run , user able write /tmp.

--edit--

running httpd directly command line not cause issue. starting httpd systemd service does

i think related answer: https://unix.stackexchange.com/questions/167835/where-apaches-tmp-located

apache might using private-tmp causes /tmp redirected /var/tmp/systemd-private--httpd.service-/