Changed isAlive() method. Renamed to isalive() and heavily modified to

used a totally different technique to determine process status.


git-svn-id: http://pexpect.svn.sourceforge.net/svnroot/pexpect/trunk@83 656d521f-e311-0410-88e0-e7920216d269

13 files changed, 92 insertions, 82 deletions

diff --git a/pexpect/Makefile b/pexpect/Makefile
index 0b82ce4..9d96945 100644
--- a/pexpect/Makefile
+++ b/pexpect/Makefile
@@ -1,6 +1,6 @@
 SHELL = /bin/sh
 
-VERSION= 0.91
+VERSION= 0.92
 #DOCGENERATOR= happydoc
 DOCGENERATOR= pydoc -w
 MANIFEST_LINES != cat MANIFEST
diff --git a/pexpect/alltests.py b/pexpect/alltests.py
index fcacfb0..8f605f0 100644
--- a/pexpect/alltests.py
+++ b/pexpect/alltests.py
@@ -17,6 +17,7 @@ modules_to_test = (
 'test_screen'
 ) 
 
+
 def suite(): 
     alltests = unittest.TestSuite() 
     for module in map(__import__, modules_to_test): 
diff --git a/pexpect/examples/ftp.py b/pexpect/examples/ftp.py
index 69909d5..bc64f92 100755
--- a/pexpect/examples/ftp.py
+++ b/pexpect/examples/ftp.py
@@ -23,8 +23,8 @@ sys.stdout.write (child.after)
 sys.stdout.flush()
 child.interact() # Escape character defaults to ^]
 
-if child.isAlive():
+if child.isalive():
     child.sendline('bye')
     child.kill(1)
-print 'Is Alive: ', child.isAlive()
+print 'Is Alive: ', child.isalive()
 
diff --git a/pexpect/examples/python.py b/pexpect/examples/python.py
index 82b507f..22b541e 100755
--- a/pexpect/examples/python.py
+++ b/pexpect/examples/python.py
@@ -18,5 +18,5 @@ print 'Escape character is \'^]\'.'
 print c.after,
 c.interact()
 c.kill(1)
-print 'isAlive:', c.isAlive()
+print 'is alive:', c.isalive()
 
diff --git a/pexpect/hash.py b/pexpect/hash.py
new file mode 100755
index 0000000..90d87f0
--- /dev/null
+++ b/pexpect/hash.py
@@ -0,0 +1,6 @@
+#!/usr/bin/env python
+import sys
+
+lines = sys.stdin.readlines()
+for line in lines:
+	sys.stdout.write ('#' + line)
diff --git a/pexpect/pexpect.py b/pexpect/pexpect.py
index ef6afd0..469db8d 100644
--- a/pexpect/pexpect.py
+++ b/pexpect/pexpect.py
@@ -130,19 +130,22 @@ class spawn:
 
         if which(self.command) == None:
             raise ExceptionPexpect ('The command was not found or was not executable: %s.' % self.command)
-
-        # This is necessary for isAlive() to work. Without this there is
-        # no portable way to tell if a child process is a zombie.
-        # Checking waitpid with WNOHANG option does not work and
-        # checking waitpid without it would block if the child is not a zombie.
-        # With this children should exit completely without going into
-        # a zombie state. Note that some UNIX flavors may send the signal
-        # before the child's pty output buffer is empty, while others
-        # may send the signal only when the buffer is empty.
-        # In the later case, isAlive() will always return true until the
-        # output buffer is empty. Use expect_eof() to consume all child output.
-        # This is not the same as the Zombie (waiting to die) problem.
-        #signal.signal(signal.SIGCHLD, signal.SIG_IGN)
+# I'm no longer using this technique to test if a process is alive.
+# First, it is not portable.
+# Second, it messes up other subsystems that use signals (such as pipes).
+# Third, signals on UNIX suck.
+#        # This is necessary for isAlive() to work. Without this there is
+#        # no portable way to tell if a child process is a zombie.
+#        # Checking waitpid with WNOHANG option does not work and
+#        # checking waitpid without it would block if the child is not a zombie.
+#        # With this children should exit completely without going into
+#        # a zombie state. Note that some UNIX flavors may send the signal
+#        # before the child's pty output buffer is empty, while others
+#        # may send the signal only when the buffer is empty.
+#        # In the later case, isAlive() will always return true until the
+#        # output buffer is empty. Use expect_eof() to consume all child output.
+#        # This is not the same as the Zombie (waiting to die) problem.
+#        #signal.signal(signal.SIGCHLD, signal.SIG_IGN)
 
         try:
             self.pid, self.child_fd = pty.fork()
@@ -461,15 +464,15 @@ class spawn:
         finally:
             termios.tcsetattr(fd, termios.TCSADRAIN, old) # restore state
         
-    def isAlive(self):
+    def isalive(self):
         """This tests if the child process is running or not.
-        It returns 1 if the child process appears to be running or
-        0 if not.
+        This returns 1 if the child process appears to be running or 0 if not.
         """
         status = os.waitpid (self.pid, os.WNOHANG)
         if status[0] == 0:
             return 1
 
+        # I didn't OR this together because I want hooks for debugging.
         if os.WIFEXITED (status[1]):
             return 0
         elif os.WIFSTOPPED (status[1]):
@@ -479,36 +482,36 @@ class spawn:
         else:
             return 1
 
-    def isAliveOld(self):
-        """This tests if the child process is running or not.
-        It returns 1 if the child process appears to be running or
-        0 if not. This checks the process list to see if the pid is
-        there. In theory, the original child could have died and the
-        pid could have been reused by some other process. This is
-        unlikely, but I can find no portable way to make sure.
-        Also, this is not POSIX portable way to check, but
-        UNIX provides no standard way to test if a given pid is
-        running or not. By convention most modern UNIX systems will
-        respond to signal 0.
-        """
-        old_signal = signal.getsignal (signal.SIGCHLD)
-        if old_signal is None:
-            raise ExceptionPexpect ('Existing signal handler is non-Python')
-        #signal.signal(signal.SIGCHLD, signal.SIG_IGN)
-        try:
-            print "stuff2"
-            os.kill (self.pid, 0)
-            print "stuff3"
-            signal.signal(signal.SIGCHLD, old_signal)
-            return 1
-        except OSError, e:
-            print str(e)
-            signal.signal(signal.SIGCHLD, old_signal)
-            return 0
-            ###return e.errno == errno.EPERM
-            ### For some reason I got this exception printed even though
-            ### I am explicitly catching OSError. Noah doth halucinate?
-            ###     OSError: [Errno 3] No such process
+#    def isAlive(self):
+#        """This tests if the child process is running or not.
+#        It returns 1 if the child process appears to be running or
+#        0 if not. This checks the process list to see if the pid is
+#        there. In theory, the original child could have died and the
+#        pid could have been reused by some other process. This is
+#        unlikely, but I can find no portable way to make sure.
+#        Also, this is not POSIX portable way to check, but
+#        UNIX provides no standard way to test if a given pid is
+#        running or not. By convention most modern UNIX systems will
+#        respond to signal 0.
+#        """
+#        old_signal = signal.getsignal (signal.SIGCHLD)
+#        if old_signal is None:
+#            raise ExceptionPexpect ('Existing signal handler is non-Python')
+#        #signal.signal(signal.SIGCHLD, signal.SIG_IGN)
+#        try:
+#            print "stuff2"
+#            os.kill (self.pid, 0)
+#            print "stuff3"
+#            signal.signal(signal.SIGCHLD, old_signal)
+#            return 1
+#        except OSError, e:
+#            print str(e)
+#            signal.signal(signal.SIGCHLD, old_signal)
+#            return 0
+#            ###return e.errno == errno.EPERM
+#            ### For some reason I got this exception printed even though
+#            ### I am explicitly catching OSError. Noah doth halucinate?
+#            ###     OSError: [Errno 3] No such process
 
     def kill(self, sig):
         """This sends the given signal to the child application.
diff --git a/pexpect/setup.py b/pexpect/setup.py
index 0f66bee..b7836ae 100644
--- a/pexpect/setup.py
+++ b/pexpect/setup.py
@@ -4,7 +4,7 @@ $Date$
 '''
 from distutils.core import setup
 setup (name='pexpect',
-	version='0.91',
+	version='0.92',
 	py_modules=['pexpect'],
 	description='Pexpect, a pure Python Expect allows control of other applications.',
 	author='Noah Spurrier',
diff --git a/pexpect/tests/test_constructor.py b/pexpect/tests/test_constructor.py
index 85262fe..a302fcd 100755
--- a/pexpect/tests/test_constructor.py
+++ b/pexpect/tests/test_constructor.py
@@ -10,8 +10,8 @@ class TestCaseConstructor(unittest.TestCase):
 	the same results for different styles of invoking __init__().
 	This assumes that the root directory / is static during the test.
 	"""
-        p1 = pexpect.spawn('/bin/ls -l /bin')
-        p2 = pexpect.spawn('/bin/ls' ,['-l', '/bin'])
+        p1 = pexpect.spawn('ls -l')
+        p2 = pexpect.spawn('ls' ,['-l'])
 	p1.expect (pexpect.EOF)
 	p2.expect (pexpect.EOF)
         assert (p1.before == p2.before)
diff --git a/pexpect/tests/test_destructor.py b/pexpect/tests/test_destructor.py
index 2c4d2d1..e6c1d27 100755
--- a/pexpect/tests/test_destructor.py
+++ b/pexpect/tests/test_destructor.py
@@ -7,25 +7,25 @@ class TestCaseDestructor(unittest.TestCase):
     #def runTest (self):
         
     def test_destructor (self):
-        p1 = pexpect.spawn('/bin/ls -l')
-        p2 = pexpect.spawn('/bin/ls -l')
-        p3 = pexpect.spawn('/bin/ls -l')
+        p1 = pexpect.spawn('ls -l')
+        p2 = pexpect.spawn('ls -l')
+        p3 = pexpect.spawn('ls -l')
         fd_t1 = (p1.child_fd,p2.child_fd,p3.child_fd)
         p1 = None
         p2 = None
         p3 = None
         gc.collect()
-        p1 = pexpect.spawn('/bin/ls -l')
-        p2 = pexpect.spawn('/bin/ls -l')
-        p3 = pexpect.spawn('/bin/ls -l')
+        p1 = pexpect.spawn('ls -l')
+        p2 = pexpect.spawn('ls -l')
+        p3 = pexpect.spawn('ls -l')
         fd_t2 = (p1.child_fd,p2.child_fd,p3.child_fd)
         del (p1)
         del (p3)
         del (p2)
         gc.collect()
-        p1 = pexpect.spawn('/bin/ls -l')
-        p2 = pexpect.spawn('/bin/ls -l')
-        p3 = pexpect.spawn('/bin/ls -l')
+        p1 = pexpect.spawn('ls -l')
+        p2 = pexpect.spawn('ls -l')
+        p3 = pexpect.spawn('ls -l')
         fd_t3 = (p1.child_fd,p2.child_fd,p3.child_fd)
 
         assert (fd_t1 == fd_t2 == fd_t3)
diff --git a/pexpect/tests/test_expect.py b/pexpect/tests/test_expect.py
index a657d72..957b703 100755
--- a/pexpect/tests/test_expect.py
+++ b/pexpect/tests/test_expect.py
@@ -8,9 +8,9 @@ class ExpectTestCase(unittest.TestCase):
     #def runTest (self):
         
     def test_expect (self):
-        the_old_way = commands.getoutput('/bin/ls -l')
+        the_old_way = commands.getoutput('ls -l')
 
-        p = pexpect.spawn('/bin/ls -l')
+        p = pexpect.spawn('ls -l')
         the_new_way = ''
         try:
                 while 1:
@@ -23,9 +23,9 @@ class ExpectTestCase(unittest.TestCase):
         assert the_old_way == the_new_way
 
     def test_expect_exact (self):
-        the_old_way = commands.getoutput('/bin/ls -l')
+        the_old_way = commands.getoutput('ls -l')
 
-        p = pexpect.spawn('/bin/ls -l')
+        p = pexpect.spawn('ls -l')
         try:
                 the_new_way = ''
                 while 1:
@@ -38,9 +38,9 @@ class ExpectTestCase(unittest.TestCase):
         assert the_old_way == the_new_way
 
     def test_expect_eof (self):
-        the_old_way = commands.getoutput('/bin/ls -l')
+        the_old_way = commands.getoutput('ls -l')
 
-        p = pexpect.spawn('/bin/ls -l')
+        p = pexpect.spawn('ls -l')
         p.expect(pexpect.EOF) # This basically tells it to read everything.
         the_new_way = p.before
         the_new_way = the_new_way.replace('\r','')
@@ -49,7 +49,7 @@ class ExpectTestCase(unittest.TestCase):
         assert the_old_way == the_new_way
 
     def test_unexpected_eof (self):
-        p = pexpect.spawn('/bin/ls -l')
+        p = pexpect.spawn('ls -l')
         try:
             p.expect('ZXYXZ') # Probably never see this in ls output.
         except pexpect.EOF, e:
diff --git a/pexpect/tests/test_is_alive.py b/pexpect/tests/test_is_alive.py
index f132b14..3865fcd 100755
--- a/pexpect/tests/test_is_alive.py
+++ b/pexpect/tests/test_is_alive.py
@@ -5,28 +5,28 @@ import sys
 
 class IsAliveTestCase(unittest.TestCase):
         
-    def test_expect_is_alive1 (self):
-        p = pexpect.spawn('/bin/ls')
+    def test_expect_isalive1 (self):
+        p = pexpect.spawn('ls')
         p.expect(pexpect.EOF)
-        if p.isAlive():
+        if p.isalive():
             self.fail ('Child process is not dead. It should be.')
 
-    def test_expect_is_alive2 (self):
-        p = pexpect.spawn('/bin/cat')
-        if not p.isAlive():
+    def test_expect_isalive2 (self):
+        p = pexpect.spawn('cat')
+        if not p.isalive():
             self.fail ('Child process is not alive. It should be.')
         p.kill(1)
         p.expect(pexpect.EOF)
-        if p.isAlive():
+        if p.isalive():
             self.fail ('Child process is not dead. It should be.')
 
-    def test_expect_is_alive3 (self):
-        p = pexpect.spawn('/bin/cat')
-        if not p.isAlive():
+    def test_expect_isalive3 (self):
+        p = pexpect.spawn('cat')
+        if not p.isalive():
             self.fail ('Child process is not alive. It should be.')
         p.kill(9)
         p.expect(pexpect.EOF)
-        if p.isAlive():
+        if p.isalive():
             self.fail ('Child process is not dead. It should be.')
 
 if __name__ == '__main__':
diff --git a/pexpect/tests/test_log.py b/pexpect/tests/test_log.py
index 96495df..4e4b170 100755
--- a/pexpect/tests/test_log.py
+++ b/pexpect/tests/test_log.py
@@ -10,7 +10,7 @@ class TestCaseLog(unittest.TestCase):
     def test_log (self):
 	log_message = 'This is a test.'
 	filename = tempfile.mktemp()
-        p = pexpect.spawn('/bin/echo', [log_message])
+        p = pexpect.spawn('echo', [log_message])
 	p.log_open (filename)
 	p.expect (pexpect.EOF)
 	p.log_close()
diff --git a/pexpect/tests/test_run_out_of_pty.py b/pexpect/tests/test_run_out_of_pty.py
index 082397b..18eac41 100755
--- a/pexpect/tests/test_run_out_of_pty.py
+++ b/pexpect/tests/test_run_out_of_pty.py
@@ -13,7 +13,7 @@ class ExpectTestCase(unittest.TestCase):
 	plist=[]
         for count in range (0,1000):
 		try:
-			plist.append (pexpect.spawn('/bin/ls -l'))
+			plist.append (pexpect.spawn('ls -l'))
 		except pexpect.ExceptionPexpect, e:
 			return
 		except Exception, e: