El código y los registros han cambiado mucho (debido a una gran reescritura) desde que se hizo la pregunta.

Cuando mi código (a continuación) se ejecuta en Windows (tanto mi computadora portátil como AppVeyor CI), hace lo que se supone que debe hacer. Pero en Linux (VM en TravisCI), me arroja un error de permiso denegado.

Error:

$ sudo python3 test.py
Testing espeak4py
Testing wait4prev
Traceback (most recent call last):
  File "test.py", line 10, in <module>
    mySpeaker.say('Hello, World!')
  File "/home/travis/build/sayak-brm/espeak4py/espeak4py/__init__.py", line 35, in say
    self.prevproc = subprocess.Popen(cmd, executable=self.executable, cwd=os.path.dirname(os.path.abspath(__file__)))
  File "/usr/lib/python3.2/subprocess.py", line 745, in __init__
    restore_signals, start_new_session)
  File "/usr/lib/python3.2/subprocess.py", line 1361, in _execute_child
    raise child_exception_type(errno_num, err_msg)
OSError: [Errno 13] Permission denied
The command "sudo python3 test.py" exited with 1.

Código:

espeak4py /en eso.py:

#! python3
import subprocess
import os
import platform

class Speaker:
    def __init__(self, voice="en", wpm=120, pitch=80):
        self.prevproc = None
        self.voice = voice
        self.wpm = wpm
        self.pitch = pitch
        if platform.system() == 'Windows': self.executable = os.path.dirname(os.path.abspath(__file__)) + "/espeak.exe"
        else: self.executable = os.path.dirname(os.path.abspath(__file__)) + "/espeak"

    def generateCmd(self, phrase):
        cmd = [
            self.executable,
            "--path=.",
            "-v", self.voice,
            "-p", self.pitch,
            "-s", self.wpm,
            phrase
        ]
        cmd = [str(x) for x in cmd]
        return cmd

    def say(self, phrase, wait4prev=False):
        cmd=self.generateCmd(phrase)
        if wait4prev:
            try: self.prevproc.wait()
            except AttributeError: pass
        else:
            try: self.prevproc.terminate()
            except AttributeError: pass
        self.prevproc = subprocess.Popen(cmd, executable=self.executable, cwd=os.path.dirname(os.path.abspath(__file__)))

test.py:

#! python3
import espeak4py
import time

print('Testing espeak4py\n')
print('Testing wait4prev')

mySpeaker = espeak4py.Speaker()

mySpeaker.say('Hello, World!')
time.sleep(1)
mySpeaker.say('Interrupted!')
time.sleep(3)

mySpeaker.say('Hello, World!')
time.sleep(1)
mySpeaker.say('Not Interrupted.', wait4prev=True)
time.sleep(5)

print('Testing pitch')

myHighPitchedSpeaker = espeak4py.Speaker(pitch=120)
myHighPitchedSpeaker.say('I am a demo of the say function')
time.sleep(5)

print('Testing wpm')

myFastSpeaker = espeak4py.Speaker(wpm=140)
myFastSpeaker.say('I am a demo of the say function')
time.sleep(5)

print('Testing voice')

mySpanishSpeaker = espeak4py.Speaker(voice='es')
mySpanishSpeaker.say('Hola. Como estas?')

print('Testing Completed.')

No entiendo por qué funciona solo en una plataforma y no en la otra.

Travis CI Logs:https://travis-ci.org/sayak-brm/espeak4py

AppVeyor Logs:https://ci.appveyor.com/project/sayak-brm/espeak4py

GitHub:https://sayak-brm.github.io/espeak4py

Tengo las salidas dels -l como @zvone recomienda:

$ ls -l
total 48
-rw-rw-r-- 1 travis travis   500 Sep 29 20:14 appveyor.yml
drwxrwxr-x 3 travis travis  4096 Sep 29 20:14 espeak4py
-rw-rw-r-- 1 travis travis 32400 Sep 29 20:14 LICENSE.md
-rw-rw-r-- 1 travis travis  2298 Sep 29 20:14 README.md
-rw-rw-r-- 1 travis travis     0 Sep 29 20:14 requirements.txt
-rw-rw-r-- 1 travis travis   759 Sep 29 20:14 test.py

$ ls -l espeak4py
total 592
-rw-rw-r-- 1 travis travis 276306 Sep 29 20:14 espeak
drwxrwxr-x 5 travis travis   4096 Sep 29 20:14 espeak-data
-rw-rw-r-- 1 travis travis 319488 Sep 29 20:14 espeak.exe
-rw-rw-r-- 1 travis travis   1125 Sep 29 20:14 __init__.py