objects should be opened in binary or text mode. The default value
for \var{mode} is \code{'t'}.
+Also, for each of these variants, on \UNIX, \var{cmd} may be a sequence, in
+which case arguments will be passed directly to the program without shell
+intervention (as with \function{os.spawnv()}). If \var{cmd} is a string it will
+be passed to the shell (as with \function{os.system()}).
+
These methods do not make it possible to retrieve the return code from
the child processes. The only way to control the input and output
streams and also retrieve the return codes is to use the
\begin{funcdesc}{popen4}{cmd\optional{, mode\optional{, bufsize}}}
Executes \var{cmd} as a sub-process. Returns the file objects
\code{(\var{child_stdin}, \var{child_stdout_and_stderr})}.
+Availability: \UNIX, Windows.
+\versionadded{2.0}
+\end{funcdesc}
(Note that \code{\var{child_stdin}, \var{child_stdout}, and
\var{child_stderr}} are named from the point of view of the child
process, i.e. \var{child_stdin} is the child's standard input.)
-Availability: \UNIX, Windows.
-\versionadded{2.0}
-\end{funcdesc}
-
This functionality is also available in the \refmodule{popen2} module
using functions of the same names, but the return values of those
functions have a different order.
if _exists("fork"):
if not _exists("popen2"):
def popen2(cmd, mode="t", bufsize=-1):
+ """Execute the shell command 'cmd' in a sub-process. On UNIX, 'cmd'
+ may be a sequence, in which case arguments will be passed directly to
+ the program without shell intervention (as with os.spawnv()). If 'cmd'
+ is a string it will be passed to the shell (as with os.system()). If
+ 'bufsize' is specified, it sets the buffer size for the I/O pipes. The
+ file objects (child_stdin, child_stdout) are returned."""
import popen2
stdout, stdin = popen2.popen2(cmd, bufsize)
return stdin, stdout
if not _exists("popen3"):
def popen3(cmd, mode="t", bufsize=-1):
+ """Execute the shell command 'cmd' in a sub-process. On UNIX, 'cmd'
+ may be a sequence, in which case arguments will be passed directly to
+ the program without shell intervention (as with os.spawnv()). If 'cmd'
+ is a string it will be passed to the shell (as with os.system()). If
+ 'bufsize' is specified, it sets the buffer size for the I/O pipes. The
+ file objects (child_stdin, child_stdout, child_stderr) are returned."""
import popen2
stdout, stdin, stderr = popen2.popen3(cmd, bufsize)
return stdin, stdout, stderr
if not _exists("popen4"):
def popen4(cmd, mode="t", bufsize=-1):
+ """Execute the shell command 'cmd' in a sub-process. On UNIX, 'cmd'
+ may be a sequence, in which case arguments will be passed directly to
+ the program without shell intervention (as with os.spawnv()). If 'cmd'
+ is a string it will be passed to the shell (as with os.system()). If
+ 'bufsize' is specified, it sets the buffer size for the I/O pipes. The
+ file objects (child_stdin, child_stdout_stderr) are returned."""
import popen2
stdout, stdin = popen2.popen4(cmd, bufsize)
return stdin, stdout
def __init__(self, cmd, capturestderr=False, bufsize=-1):
"""The parameter 'cmd' is the shell command to execute in a
- sub-process. The 'capturestderr' flag, if true, specifies that
- the object should capture standard error output of the child process.
- The default is false. If the 'bufsize' parameter is specified, it
- specifies the size of the I/O buffers to/from the child process."""
+ sub-process. On UNIX, 'cmd' may be a sequence, in which case arguments
+ will be passed directly to the program without shell intervention (as
+ with os.spawnv()). If 'cmd' is a string it will be passed to the shell
+ (as with os.system()). The 'capturestderr' flag, if true, specifies
+ that the object should capture standard error output of the child
+ process. The default is false. If the 'bufsize' parameter is
+ specified, it specifies the size of the I/O buffers to/from the child
+ process."""
_cleanup()
p2cread, p2cwrite = os.pipe()
c2pread, c2pwrite = os.pipe()
del Popen3, Popen4
def popen2(cmd, bufsize=-1, mode='t'):
- """Execute the shell command 'cmd' in a sub-process. If 'bufsize' is
- specified, it sets the buffer size for the I/O pipes. The file objects
- (child_stdout, child_stdin) are returned."""
+ """Execute the shell command 'cmd' in a sub-process. On UNIX, 'cmd' may
+ be a sequence, in which case arguments will be passed directly to the
+ program without shell intervention (as with os.spawnv()). If 'cmd' is a
+ string it will be passed to the shell (as with os.system()). If
+ 'bufsize' is specified, it sets the buffer size for the I/O pipes. The
+ file objects (child_stdout, child_stdin) are returned."""
w, r = os.popen2(cmd, mode, bufsize)
return r, w
def popen3(cmd, bufsize=-1, mode='t'):
- """Execute the shell command 'cmd' in a sub-process. If 'bufsize' is
- specified, it sets the buffer size for the I/O pipes. The file objects
- (child_stdout, child_stdin, child_stderr) are returned."""
+ """Execute the shell command 'cmd' in a sub-process. On UNIX, 'cmd' may
+ be a sequence, in which case arguments will be passed directly to the
+ program without shell intervention (as with os.spawnv()). If 'cmd' is a
+ string it will be passed to the shell (as with os.system()). If
+ 'bufsize' is specified, it sets the buffer size for the I/O pipes. The
+ file objects (child_stdout, child_stdin, child_stderr) are returned."""
w, r, e = os.popen3(cmd, mode, bufsize)
return r, w, e
def popen4(cmd, bufsize=-1, mode='t'):
- """Execute the shell command 'cmd' in a sub-process. If 'bufsize' is
- specified, it sets the buffer size for the I/O pipes. The file objects
- (child_stdout_stderr, child_stdin) are returned."""
+ """Execute the shell command 'cmd' in a sub-process. On UNIX, 'cmd' may
+ be a sequence, in which case arguments will be passed directly to the
+ program without shell intervention (as with os.spawnv()). If 'cmd' is a
+ string it will be passed to the shell (as with os.system()). If
+ 'bufsize' is specified, it sets the buffer size for the I/O pipes. The
+ file objects (child_stdout_stderr, child_stdin) are returned."""
w, r = os.popen4(cmd, mode, bufsize)
return r, w
else:
def popen2(cmd, bufsize=-1, mode='t'):
- """Execute the shell command 'cmd' in a sub-process. If 'bufsize' is
- specified, it sets the buffer size for the I/O pipes. The file objects
- (child_stdout, child_stdin) are returned."""
+ """Execute the shell command 'cmd' in a sub-process. On UNIX, 'cmd' may
+ be a sequence, in which case arguments will be passed directly to the
+ program without shell intervention (as with os.spawnv()). If 'cmd' is a
+ string it will be passed to the shell (as with os.system()). If
+ 'bufsize' is specified, it sets the buffer size for the I/O pipes. The
+ file objects (child_stdout, child_stdin) are returned."""
inst = Popen3(cmd, False, bufsize)
return inst.fromchild, inst.tochild
def popen3(cmd, bufsize=-1, mode='t'):
- """Execute the shell command 'cmd' in a sub-process. If 'bufsize' is
- specified, it sets the buffer size for the I/O pipes. The file objects
- (child_stdout, child_stdin, child_stderr) are returned."""
+ """Execute the shell command 'cmd' in a sub-process. On UNIX, 'cmd' may
+ be a sequence, in which case arguments will be passed directly to the
+ program without shell intervention (as with os.spawnv()). If 'cmd' is a
+ string it will be passed to the shell (as with os.system()). If
+ 'bufsize' is specified, it sets the buffer size for the I/O pipes. The
+ file objects (child_stdout, child_stdin, child_stderr) are returned."""
inst = Popen3(cmd, True, bufsize)
return inst.fromchild, inst.tochild, inst.childerr
def popen4(cmd, bufsize=-1, mode='t'):
- """Execute the shell command 'cmd' in a sub-process. If 'bufsize' is
- specified, it sets the buffer size for the I/O pipes. The file objects
- (child_stdout_stderr, child_stdin) are returned."""
+ """Execute the shell command 'cmd' in a sub-process. On UNIX, 'cmd' may
+ be a sequence, in which case arguments will be passed directly to the
+ program without shell intervention (as with os.spawnv()). If 'cmd' is a
+ string it will be passed to the shell (as with os.system()). If
+ 'bufsize' is specified, it sets the buffer size for the I/O pipes. The
+ file objects (child_stdout_stderr, child_stdin) are returned."""
inst = Popen4(cmd, bufsize)
return inst.fromchild, inst.tochild