I've been struggling with GStreamer for a while because I can't find any C# examples/tutorials.
As far as I know, Gstreamer uses pipelines in order to decode and then be able to send, for instance a song, to the speakers, but I tried the following, which didn't work:
Gst.Element pipeline;
string path = #"some_path.mp3";
string command = "filesrc location=" + path + " ! oggdemux ! vorbisdec ! audioconvert ! gconfaudiosink";
pipeline = Gst.Parse.Launch(command);
pipeline.SetState(Gst.State.Playing);
However, it raises an exception in the Gst.Parse.Launch line
Does anyone know any good application example, and/or can actually post some code, so I can start getting used to the library? Also, if you can tell me what's wrong on the code above, I'd be thankful
Without further ado,
Regards
Just change your command string to "filesrc location=" + path + " ! decodebin2 ! gconfaudiosink", that should work.
On a side note you should use the gst-launch tool on the command line to check if your pipeline is working and to debug it. Also use gst-inspect to find which plugins are available on your system and what is their functionality.
Related
So I am trying to write a cd -like program that can be executed using cmd and after it exits the working directory of the calling cmd process should be changed.
Now before this post is flagged as a duplicate: I am aware of this and this question that were asked for pretty much this exact problem but using Linux instead of Windows as well as being pretty broad and unspecific, and I am aware that similar limitations apply to Windows as well (changing the working directory of my process will not change the parent’s working directory).
There is actually is a working solution to this for linux. However it is using gdb for this, and I would like to achieve this task using only built-in Windows utilities (WinAPI, dotNET, etc.).
What I have tried so far
I did manage to use Cheat Engine and the OpenProcess() / WriteProcessMemory() WinAPI funtions to successfully override cmd's working directory. However this solution feels sloppy and doesn't work well (or at least requires more work to be put into.)
My question
Is there a different (maybe simpler?) way on Windows to achieve this? Like a way to invoke/inject code to the cmd process to execute cd whatever\directory\I\want directly without overriding its memory? I have seen the CreateRemoteThread() functions however I didn't manage to find a way to put them to use.
FYI: I am mainly using C# but C/C++ solutions should help too as long as they are based on the native Microsoft libraries.
This post describes a Windows implementation of a function that launches a child process, creates pipes to stdin and stdout from which a command is sent, and a response is returned. Finally, once all response is captured the child process is terminated. If this sounds familiar it is similar in concept to Linux's popen() function with the exception that this implementation was specifically created to capture the response into a buffer of any command that returns one. (Also included is a variant for use when no-response is expected or needed.)
The full source can be adapted for use within a standalone executable, or as an API. (.dll) Either way, the resulting functions accept and process any command using standard Windows CMD syntax. The function cmd_rsp(...) returns the Windows response via stdout into a self-sizing buffer.
The exported prototypes are:
int __declspec(dllexport) cmd_rsp(const char *command, char **chunk, unsigned int size);
int __declspec(dllexport) cmd_no_rsp(const char *command);
A simple use case when capturing a response:
#include "cmd_rsp.h"
int main(void)
{
char *buf = {0};
buf = calloc(100, 1);//initialize to some initial size
if(!buf)return 0;
cmd_rsp("dir /s", &buf, 100);//buffer will grow to accommodate response as needed.
printf("%s", buf);
free(buf);
return 0;
}
A simple use case when response is not needed:
#include "cmd_rsp.h"
int main(void)
{
cmd_no_rsp("cd C:\\dir1\\dir2");
return 0;
}
A detailed description of purpose and usage is described in the link provided above. To illustrate, here are a few sample command inputs, each in this case change the working directory, then execute a command from that directory:
A command to change to sqlite directory, then execute a query:
cd c:\\tempExtract\\sqlite\\Tools\\sqlite-tools-win32-x86-3250300 && sqlite3.exe .\\extract.db \"select * from event, eventdata where eventType=38 and eventdata .eventid=event.eventid\
A command to change to teraterm directory, then execute a script:
"c:\\Program Files (x86)\\teraterm\" && ttpmacro c:\\DevPhys\\LPCR_2\\play\\Play.ttl
A command to change directory then execute a command to send multiple digital acquisition channel settings.
cd C:\\Dir1\\Dir2\\Dir3\\support\\Exes\\WriteDigChannel && .\\WriteDigChannel.exe P1_CH0 1 && .\\WriteDigChannel.exe P1_C H0 0 && .\\WriteDigChannel.exe P1_CH0 1
A recursive directory search from a specified location:
cd C:\\dir1\\dir2 && dir /s /b
I got it working. As was suggested SendInput finally did the trick.
I used a combination of WinAPI calls to GetForegroundWindow() / SetForegroundWindow() and the Windows Forms System.Windows.Forms.SendKeys.SendWait() Method to achieve what I wanted:
Upon calling my cd-wrapper program (sd.exe) and providing my custom target directory (~/ home) it generates the corresponding command along with the "Enter-Pressed-Event" to be sent to it's parent cmd process.
Here's the complete C# code:
if (args.Length != 1)
{
Console.WriteLine(Directory.GetCurrentDirectory());
return;
}
string targetDirectory = args[0];
string command = string.Empty;
if (targetDirectory.Equals("~"))
{
command = #"pushd C:\Users\fred\Desktop";
}
else if (!Directory.Exists(targetDirectory))
{
Console.WriteLine("I/O Error: No such file or directory.");
return;
}
else
{
command = #"cd " + targetDirectory;
}
Target target = Target.Create(Process.GetCurrentProcess().GetParentProcess());
target.SendKeys(command + "{ENTER}", true);
Note that I kind of started to write a complete Framework for this and similar problems alongside this project that contains all my different approaches to this question and the low level WinAPI calls as well as the Extension methods to get the parent process :D
As it would be a bit overkill to paste all of it's code in this answer, here's the GitHub. If I can find the time I'll go ahead and optimize the code, but for now this'll do. Hope this helps anyone encountering a similar problem :)
Edit:
An even "cleaner" way is to use dll injection to directly make cmd switch it's working directory. While it is a lot harder to get working it has the advantage of not littering the cmd command history as compared to the approach described above. In addition to that cmd seems to be aware of any changes to it's current working directory, so it automatically updates the prompt text. Once I have a fully working example, that allows to dynamically specify the target directory I will post it here :)
I am facing issue with perforce api (.net), as i am unable to pull sync logs in real time.
- What am I trying to do
I am trying to pull real time logs as Sync is triggered using the
Perforce.P4.Client.SyncFiles() command. Similar to the P4V GUI Logs, which update when we try to sync any files.
- What is happening now
As the output is generated only after the command is done execution its not something intended for.
Also tried looking into Perforce.P4.P4Server.RunCommand() which does provide detailed report but only after the execution of the command.
Looked into this
Reason is -
I am trying to add a status update to the Tool i am working on which shows which Perforce file is currently being sync'd.
Please advise. Thanks in Advance.
-Bharath
In the C++ client API (which is what P4V is built on), the client receives an OutputInfo callback (or OutputStat in tagged mode) for each file as it begins syncing.
Looking over the .NET documentation I think the equivalents are the P4CallBacks.InfoResultsDelegate and P4CallBacks.TaggedOutputDelegate which handle events like P4Server.InfoResultsReceived etc.
I ended up with the same issue, and I struggled quite a bit to get it to work, so I will share the solution I found:
First, you should use the P4Server class instead of the Perforce.P4.Connection. They are two classes doing more or less the same thing, but when I tried using the P4.Connection.TaggedOutputReceived events, I simply got nothing back. So instead I tried with the P4Server.TaggedOutputReceived, and there, finally, I got the TaggedOutput just like I wanted.
So, here is a small example:
P4Server p4Server = new P4Server(cwdPath); //In my case I use P4Config, so no need to set user or to login, but you can do all that with the p4Server here.
p4Server.TaggedOutputReceived += P4ServerTaggedOutputEvent;
p4Server.ErrorReceived += P4ServerErrorReceived;
bool syncSuccess=false;
try
{
P4Command syncCommand = new P4Command(p4Server, "sync", true, syncPath + "\\...");
P4CommandResult rslt = syncCommand.Run();
syncSuccess=true;
//Here you can read the content of the P4CommandResult
//But it will only be accessible when the command is finished.
}
catch (P4Exception ex) //Will be caught only when the command has failed
{
Console.WriteLine("P4Command failed: " + ex.Message);
}
And the method to handle the error messages or the taggedOutput:
private void P4ServerErrorReceived(uint cmdId, int severity, int errorNumber, string data)
{
Console.WriteLine("P4ServerErrorReceived:" + data);
}
private void P4ServerTaggedOutputEvent(uint cmdId, int ObjId, TaggedObject Obj)
{
Console.WriteLine("P4ServerTaggedOutputEvent:" + Obj["clientFile"]); //Write the synced file name.
//Note that I used this only for a 'Sync' command, for other commands, I guess there might not be any Obj["clientFile"], so you should check for that.
}
If you work with mono and use Process.ProcessName you may get wrong results on some computers.
For example instead of the process name "kwrite" you may get "kdeinit4" (seen on SUSE).
On Ubuntu I have even seen complete bullshit like "kdeinit4;5535948c (deleted)" instead of "kwrite".
Note: On other computers the result may be correct.
If I use Process.MainModule.ModuleName it retruns the same wrong name.
And if I use Process.MainModule.FileName it gives the wrong path. Apart from that these commands are EXTREMELY slow.
So whatever I try it is full of bugs.
What can I do?
The workaround can be done with two lines:
String sProcFile = String.Format("/proc/{0}/comm", proc.Id);
String sProcName = File.ReadAllText(sProcFile).Trim();
It works like a charm on all computers where ProcessName fails.
There are MULTIPLE threads here asking how to change an icon - and nearly all of them say to use a command line tool such as ResHacker - but none of them (that I have seen) explain how to do so. I read into ResHacker's help file, and I found some text which explained how to go about changing the icon of a win32 executable file.
I tried the below code, and it gave me the following error:
Code:
p.StartInfo.Arguments = "-addoverwrite " + txtProtect.Text + "," + txtProtect.Text + "," + sICOpath + "," + "ICONGROUP" + ", MAINICON, 0";
Error:
"C:\Users\Evan\Desktop\ResHacker.exe" -addoverwrite C:\Users\Evan\Desktop\output.exe,C:\Users\FARINA_EVAN\Desktop\output.exe,C:\Users\Evan\Desktop\ExeWithIcon.exe,ICONGROUP, MAINICON, 0
Error: Invalid resource type.
I realize that this is a bit... Old, but the reason this won't work is because you're trying to get the icon FROM a .exe, which doesn't work with the command line of ResHacker.
The only thing I can think of is to Extract the icon from the .exe and save it as a .ico.
Then you can do the "push."
I wasn't able to find anything on how to programmatically run ResHacker except through manipulating the command line through C# like you are attempting to do. However, to speak to the root of your question, I found a possible solution for you here that does not require ResHacker. Instead, it allows you to modify the icon through code (C# and VB.NET). Here is the link:
http://www.hackforums.net/archive/index.php/thread-422072-1.html
I am not an expert in P4.NET plugin, but I would like to show the existing workspaces for a user in a combo box, so that I can set the p4.Client to the selected workspace.
using (var p4 = new P4Connection())
{
p4.Connect();
???
}
How do I get the list of existing workspaces?
I think the command line to achieve this would be
p4 clients -m 100 -u username
If P4.Net behaves similar to the official Perforce APIs, then you would likely want to run:
p4.Run("clients", "-m 100 -u username")
or similar. Inspired by the P4Ruby documentation.
Ok I have no choice than answering my own question, because the code would be too much to insert as comments to jhwist answer. Sorry jhwist. I had no choice.
#appinger, I hope you find this answer helpful. Took me hours to figure out this api working. :)
cmbBoxPerforceWorkspaceLocation is just your combobox for your workspaces. I am using Winforms by the way.
I need to extract a shortname from the windows username. Windows username starts usually with xxxx\\username. In my code I extract the username out of the longname and save it as shortname. If your network is set differently this code might have to change accordingly.
Let me know if it worked for you.
using (var p4 = new P4Connection())
{
p4.Connect();
var longName = WindowsIdentity.GetCurrent().Name;
var shortname = longName.Substring(longName.IndexOf("\\") + 1);
var records = p4.Run("clients", "-u", shortname);
cmbBoxPerforceWorkspaceLocation.Items.Clear();
foreach (P4Record record in records.Records)
{
cmbBoxPerforceWorkspaceLocation.Items.Add(record["client"]);
}
}
P4.Net is designed to be similar to the scripting APIs, which in turn are designed around the command line interface. It definitely does not have a intuitive object-oriented interface... which is off putting at first. But if you start from the command-line (esp -ztag flag) and piece together all data/actions your app needs, you will find it pretty easy to use P4.Net. And since it's similar to all the scripting APIs, you'll find it natural to pickup Python or Ruby if you wish :-)