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wxProcess

^{generated from ../src/mod_io/process.cpp}

The objects of this class are used in conjunction with the wxExecute function. When a wxProcess object is passed to wxExecute(), its onTerminate event is called when the process terminates. This allows the program to be (asynchronously) notified about the process termination and also retrieve its exit status which is unavailable from wxExecute in the case of asynchronous execution.

wxProcess also supports IO redirection of the child process. For this, you have to call its redirect method before passing it to wxExecute. If the child process was launched successfully, inputStream, outputStream and errorStream can then be used to retrieve the streams corresponding to the child process standard output, input and error output respectively.

Constants

Name	Description
DEFAULT
REDIRECT	Turn on redirection

wxKillError

Name	Description
OK	no error
BAD_SIGNAL	no such signal
ACCESS_DENIED	permission denied
NO_PROCESS	no such process
ERROR	another, unspecified error

wxSignal

Name	Description
SIGNONE
SIGHUP
SIGINT
SIGQUIT
SIGILL
SIGTRAP
SIGABRT
SIGEMT
SIGFPE
SIGKILL
SIGBUS
SIGSEGV
SIGSYS
SIGPIPE
SIGALRM
SIGTERM

Class Methods

exists

exists(Pid) : Boolean
 

Name	Type	Default	Description
Pid	Integer		Process ID

Returns true if the given process exists in the system

kill

kill(pid, 
     signal = wxSignal.SIGNONE, 
     killChildren = false) : wxKillError
 

Name	Type	Default	Description
pid	Integer		The process ID
signal	Integer	wxSignal.SIGNONE	The signal to send to the process
killChildren	Boolean	false	Kill child processes?

Send the specified signal to the given process.

Constructor

wxProcess

wxProcess(Flag = wxProcess.DEFAULT)
 

Name	Type	Default	Description
Flag	Integer	wxProcess.DEFAULT

Constructs a new wxProcess object.

Properties

Name	Type	Description
errorAvailable	Boolean	Returns true if there is data to be read on the child process standard error stream.
errorStream	wxInputStream	Returns an input stream which corresponds to the standard error output (stderr) of the child process.
inputAvailable	Boolean	Returns true if there is data to be read on the child process standard output stream.
inputOpened	Boolean	Returns true if the child process standard output stream is opened.
inputStream	wxInputStream	It returns an input stream corresponding to the standard output stream of the subprocess. If it is null, you have not turned on the redirection
outputStream	wxOutputStream	It returns an output stream corresponding to the input stream of the subprocess. If it is null, you have not turned on the redirection.
pid	Integer	Returns the process ID of the process launched by open.

Methods

closeOutput

closeOutput()
 

Closes the output stream (the one connected to the stdin of the child process). This function can be used to indicate to the child process that there is no more data to be read - usually, a filter program will only terminate when the input stream is closed.

detach

detach()
 

Normally, a wxProcess object is destroyed when it receives the notification about the process termination. However, it might happen that the parent application ends before the external process is terminated (e.g. a window from which this external process was launched is closed by the user) and in this case it should detach.

redirect

redirect()
 

Turns on redirection. wxExecute will try to open a couple of pipes to catch the subprocess stdio. The caught input stream is returned by outputStream as a non-seekable stream. The caught output stream is returned by inputStream as a non-seekable stream.