i wan to create a program that can get the application name
i can start the program but cant get the program name
<br/><br/>
a = Process.Start("calc").Handle<br/>
MsgBox(a)<br/>
MsgBox(Process.GetProcessById(a).ToSt</ br>ring)<br/>
<br/>
it show Process with an Id of 1796 is not running, but the program already opened
Handle!=Id, and ToString() won't give you the process name:
Dim a = Process.Start("calc").Id
MsgBox(a)
MsgBox(Process.GetProcessById(a).ProcessName)
Displays a process ID in one message box, then "calc" in the next.
If you had Option Strict On, you'd have received a warning already about your mixup between Handle and Id, since Handle returns an IntPtr, but GetProcessById expects an Integer.
Related
I'm currently working on an application that run in the background and sometime create an input dialog for the user to answer. If the user doesn't interact, I'd like to close the dialog after 30 seconds. I made a QThread that act like a timer and the "finished" signal should close the dialog. I unfortunately cannot find a way to close it.
At this point I'm pretty much lost. I completely new to QThread and a beginner in PyQt5
Here is a simplified version of the code (we are inside a class running a UI):
def Myfunction(self,q):
# q : [q1,q2,q3]
self.popup = counter_thread()
self.popup.start()
self.dial = QInputDialog
self.popup.finished.connect(self.dial.close)
text, ok = self.dial.getText(self, 'Time to compute !', '%s %s %s = ?'%(q[0], q[2], q[1]))
#[...]
I tried ".close()" and others but i got this error message:
TypeError: close(self): first argument of unbound method must have type 'QWidget'
I did it in a separated function but got the same problem...
You cannot close it because the self.dial you created is just an alias (another reference) to a class, not an instance.
Also, getText() is a static function that internally creates the dialog instance, and you have no access to it.
While it is possible to get that dialog through some tricks (installing an event filter on the QApplication), there's no point in complicating things: instead of using the static function, create a full instance of QInputDialog.
def Myfunction(self,q):
# q : [q1,q2,q3]
self.popup = counter_thread()
self.dial = QInputDialog(self) # <- this is an instance!
self.dial.setInputMode(QInputDialog.TextInput)
self.dial.setWindowTitle('Time to compute !')
self.dial.setLabelText('%s %s %s = ?'%(q[0], q[2], q[1]))
self.popup.finished.connect(self.dial.reject)
self.popup.start()
if self.dial.exec():
text = self.dial.textValue()
Note that I started the thread just before showing the dialog, in the rare case it may return immediately, and also because, for the same reason, the signal should be connected before starting it.
I am simulating the passenger changeover process in metros using the Anylogic Pedestrian Library.
When passengers enter the vehicle, a seat is assigned to them from the seats available near the door (within a given distance) they entered the vehicle through, using a function called lookForSeat. If there is no more free seat available, their boolean parameter wantToSit is set to false and they will stay standing.
The parameter wantToSit is predefined for the Passenger Agent, with default value randomtrue(0.8). But even if I set it to default value = 1, I get the same error.
Then, passengers are separated using a PedSelectOutput block:
Condition 1: if ped.WantToSit = true --> they are sent to their
assigned seat coordinates (PointNode 'seatPoint', null by default)
Condition 2: true (thus, ped.WantToSit = false) --> they stay in the
standing area in the vehicle, no assigned seatPoint necessary in this case.
Now, it works pretty well, but when the majority of the seats is already occupied, suddenly the PedSelectOutput block directs a passenger with ped.wantToSit to its seating point, which gives null and I get the NullPointerException error.
Attached you find the function, the settings of PedSelectOutput and the log from the command.
As it can be seen, the PedSelectOutput sends the passenger through exit 1 (which gives the error due to calling the coordinates of a "null"), despite ped.wantToSit = false.
Any ideas, what is going wrong? For me it really looks like the function is working properly - I have been changing it the whole day until I realized that something in the PedSelectOutput block goes wrong.
Thank you in advance!
Pic 1: pedSelectOutput block and the command with the log
Pic 2: the function lookForSeat assigning the seats from the seat Collection
The problem here is a subtle one, which has caused me many hours of debugging as well. What you need to understand is that the on exit code is only executed once the agent already has a path to which it is going to exit. i.e. the selectOutput and subsequent blocks are already evaluated and only once it is determined that the agent can move to the next block then the on exit code is called. But the agent will continue on its chosen path that has been determined before the on exit code has been executed.
See the small example below:
I have a pedestrian with a variable that is true by default and a select output that checks this value
If I ran the model all pedestrians exit at the top option, as expected
If I change the variable to false on the On Exit code I might expect that all pedestrians will now exit at the second option
But they don't there is no change....
If I add the code to the on enter code then it does..
I'm all new to erlang, and i got this task:
Write a function "setalarm(T,Message)" what starts two processes at
the same time. After T miliseconds the first process sends a message
to the second process, and that message will be the Message arg.
It's forbidden to use function library, only primitives (send, receive, spawn)
Me as a novice useful to write more code, so I suggest such an option:
setalarm(T,Message)->
S = spawn(sotest,second,[]),
Pid = spawn(sotest,first,[S,T,Message]).
first(Pid,T,Message) ->
receive
after T -> Pid ! Message
end.
second() ->
receive
Message -> io:format("The message is ~p~n",[Message])
end.
I am aware that you can preform simple message passing with the following:
self() ! hello.
and you can see the message by calling:
flush().
I can also create simple processes in functions with something like:
spawn(module, function, args).
However I am not clear how one can send messages to the processes with out registering the Pid.
I have seen examples showing that you can pattern match against this in the shell to get the Pid assigned to a var, so if i create a gen_server such as:
...
start_link() ->
gen_server:start_link(?MODULE, init, []).
init(Pid) ->
{ok, Pid}.
...
I can then call it with the following from the shell:
{ok, Pid} = test_sup:start_link().
{ok,<0.143.0>}
> Pid ! test.
test
So my question is, can you send messages to Pids in the form <0.0.0> with out registering them to an atom or variable in the shell? Experimenting and searching as proved fruitless...
If you happen to need to send a message to a Pid based on the textual representation of its Pid, you can do (assuming the string is "<0.42.0>"):
list_to_pid("<0.42.0>") ! Message
This is almost only useful in the shell (where you can see the output of log messages or monitor data from something like Observer); any spawned process should normally be a child of some form of parent process to which it is linked (or monitored).
As for sending a message to something you just spawned, spawn returns a Pid, so you can assign it directly to a variable (which is not the same as registering it):
Pid = spawn(M, F, A),
Pid ! Message.
If you have the string "" to identify a pid, it is
either because you are working in the shell, and you use the representation you see, and you forgot to store this pid in a variable. Then simply use pid(X,Y,Z) to get it;
either because you did something like io_lib:format("~p",[Val]) where Val is the pid or a an erlang term which contain this pid. Then simply assign the pid to a variable (directly or extracting it from the term). It can be stored in an ets, send to another process without transformation
You should avoid to use the shell (or string) representation. One reason is that this representation is different when you ask the pid of one process from 2 different nodes as shown in the next screen capture.
I have an application that I have started developing that monitors websocket messages from all clients connected to the websocket server by relaying all messages received from the server to this application.
Problem
When I run my program (In visual studio I hit Start), it builds and starts up perfectly, and does most of the functionality the same everytime. However, I have a common occurance of a portion of code that will not run the same. Below is the small snippet of that code.
msg = "set name monitor"
SendMessage2(socket, msg, msg.Length)
msg = "set monitor 1"
SendMessage2(socket, msg, msg.Length)
Console.WriteLine("We are after our second SendMessage2 function")
I know that the two calls to SendMessage2 are always executed because visual studio's debug console will output the following
We are at the end of the SendMessage2 Sub
We are at the end of the SendMessage2 Sub
We are after our second SendMessage2 function
I also know when it executes correctly because my websocket server will either output one of the two blocks
Output when app runs correctly
Client 4 connected
New thread created
Connection received. Parsing headers.
Message from socket #4: "set name monitor"
Message from socket #4: "set monitor 1"
Output when app runs incorrectly
Client 4 connected
New thread created
Connection received. Parsing headers.
Message from socket #4: "set name monitor"
Notice how the second output is missing the second message from the monitor application.
What have I tried
Using a string variable to call the functions
Calling the functions using static string arguments (not using the variable msg)
SyncLocking the functions separately
SyncLocking inside the SendMessage2 function
Reordering the functions (swapping the strings to change behavior)
TL;DR
Why is it that even when I do not change my code, my program will execute two separate ways? Am I doing something incorrectly when calling my SendMessage2 Sub?
I am all out of ideas. I am willing to try any recommendation to fix this problem.
All code can be found on GitHub here
So I figured it out.
It is actually not the VB application that is messing up. Nor was my server. While debugging I was looking at the number of bytes received by my server and I noticed the following:
Client 4 connected
New thread created
Connection received. Parsing headers.
bytes read: 25
Message from socket #4: "set name monitor"
bytes read: 22
Message from socket #4: "set monitor 1"
Ok great we have 25 bytes from set name monitor and 22 bytes from set monitor 1
Client 4 connected
New thread created
Connection received. Parsing headers.
bytes read: 47
Message from socket #4: "set name monitor"
And boom. Both programs were doing their jobs, sending the correct number of bytes every time and reading the correct number. However, the VB application is sending them so quickly back to back that my server was reading all 47 bytes at a time instead of the separate 25 and 22 bytes.
Solution
I solved this problem by implementing a secondary buffer in my server to store off all bytes after the first message should multiple messages by group like this. Now I check if my secondaryBuffer is empty before reading in new bytes.
Here is a portion of the code used to solve the problem
/*Byte Check*/
for (j=0; j < bytes; j++) {
if (j == 0)
continue;
if (readBuffer[j] == '\x81' && readBuffer[j-1] == '\x00' && readBuffer[j-2] == '\x00') {
secondaryBytes = bytes - j;
printf("Potential second message attached to this message\nCopying it to the secondary buffer.\n");
memcpy(secondaryBuffer, readBuffer + j, secondaryBytes);
break;
}//END IF
}//END FOR LOOP
/**/