How can I capture output from the Windows cmd shell? - php

Question

Is there any way with, say Perl or PHP, that I can grab output from another process that outputs to the Windows cmd shell? I have a game server that outputs certain information, for example say 'player finished track in 43s' and I want to grab that line and use Perl or PHP to send a request to a webserver to update ranks on a web page. Is there a way to grab that output pipe in Perl or PHP? Or could I achieve this using C++ Windows API maybe?
Let me clarify here: I want to execute a seperate Perl or PHP script that grabs output from the Windows cmd shell, and the output that is being displayed to the Windows cmd shell is coming from a different process.

Answer 1

You could use IPC::Open3 to read from the other process' standard output. Note that inter-process communication assumes a parent/child relationship between the processes. If that's not the case... I'm not aware of a mechanism for attaching to the output of a pre-existing process. In that case you may need to alter the producer to write data to a log file (or database) that your application can read from.

Answer 2

If all you care about is STDOUT, you can just use open2 from IPC::Open2:
#!/usr/bin/perl
use strict;
use warnings;
use IPC::Open2;
#if there are arguments pretend to be the server
#for this example
if (#ARGV) {
local $| = 1;
for my $i (1 .. 100) {
print "pid $$ iter $i\n";
sleep 1;
}
exit;
}
#run perl with the current script as its argument,
#pass in an arg so that we trigger the behaviour
#above
open2 my $out, my $in, $^X, $0, 1
or die "could not run '$^X $0 1': $!\n";
while (<$out>) {
s/[\r\n]//g;
print "pid $$ saw [$_]\n";
}

Answer 3

You need to start your server within Perl:
my $server_out = `server.exe`; # Note the backticks.
Now $server_out contains the output of server.exe. But the trick here is that you have to wait until server.exe exits to get the out put.
Try IPC::Run (which is not a core module)
use English;
use IPC::Run;
my ($stdout, $stderr);
IPC::Run::run([$cmd, $arg1, $arg2, $argN], \undef, \$stdout, $stderr);
while(<$stdout>) {
print "Cmd said $_\n";
}
Note: Code not tested.
Found the info here.

Answer 4

Capturing the output in Perl is as simple as:
$output = qx(command);
or
$output = `command`; # backticks
Refer: perldoc perlop

Answer 5

This code redirects the STDOUT of a console application to a stringlist, which you can use on a memo for example. It's Delphi code, but in C++ the basic idea is exactly the same.
I use it to run console applications hidden, while redirecting the output to my own application, to show in a pane. It adds a new line to AStrings as soon as data comes in, so you'll have access to the output of the other application before it finishes.
procedure RunConsoleApp(const CommandLine: string; AStrings: TStrings);
type
TCharBuffer = array[0..MaxInt div SizeOf(Char) - 1] of Char;
const
MaxBufSize = 1024;
var
I: Longword;
SI: TStartupInfo;
PI: TProcessInformation;
SA: PSecurityAttributes;
SD: PSECURITY_DESCRIPTOR;
NewStdIn: THandle;
NewStdOut: THandle;
ReadStdOut: THandle;
WriteStdIn: THandle;
Buffer: ^TCharBuffer;
BufferSize: Cardinal;
Last: WideString;
Str: WideString;
ExitCode_: DWORD;
Bread: DWORD;
Avail: DWORD;
begin
GetMem(SA, SizeOf(TSecurityAttributes));
case Win32Platform of
VER_PLATFORM_WIN32_NT:
begin
GetMem(SD, SizeOf(SECURITY_DESCRIPTOR));
SysUtils.Win32Check(InitializeSecurityDescriptor(SD, SECURITY_DESCRIPTOR_REVISION));
SysUtils.Win32Check(SetSecurityDescriptorDacl(SD, True, nil, False));
SA.lpSecurityDescriptor := SD;
end; {end VER_PLATFORM_WIN32_NT}
else
SA.lpSecurityDescriptor := nil;
end; {end case}
SA.nLength := SizeOf(SECURITY_ATTRIBUTES);
SA.bInheritHandle := True;
SysUtils.Win32Check(CreatePipe(NewStdIn, WriteStdIn, SA, 0));
if not CreatePipe(ReadStdOut, NewStdOut, SA, 0) then
begin
CloseHandle(NewStdIn);
CloseHandle(WriteStdIn);
SysUtils.RaiseLastWin32Error;
end; {end if}
GetStartupInfo(SI);
SI.dwFlags := STARTF_USESTDHANDLES or STARTF_USESHOWWINDOW;
SI.wShowWindow := {SW_SHOWNORMAL} SW_HIDE;
SI.hStdOutput := NewStdOut;
SI.hStdError := NewStdOut;
SI.hStdInput := NewStdIn;
if not CreateProcess(nil, PChar(CommandLine), nil, nil, True, CREATE_NEW_CONSOLE, nil, nil, SI, PI) then
begin
CloseHandle(NewStdIn);
CloseHandle(NewStdOut);
CloseHandle(ReadStdOut);
CloseHandle(WriteStdIn);
SysUtils.RaiseLastWin32Error;
end; {end if}
Last := '';
BufferSize := MaxBufSize;
Buffer := AllocMem(BufferSize);
try
repeat
SysUtils.Win32Check(GetExitCodeProcess(PI.hProcess, ExitCode_));
PeekNamedPipe(ReadStdOut, Buffer, BufferSize, #Bread, #Avail, nil);
if (Bread <> 0) then
begin
if (BufferSize < Avail) then
begin
BufferSize := Avail;
ReallocMem(Buffer, BufferSize);
end; {end if}
FillChar(Buffer^, BufferSize, #0);
Windows.ReadFile(ReadStdOut, Buffer^, BufferSize, Bread, nil);
Str := Last;
I := 0;
while (I < Bread) do
begin
case Buffer^[I] of
#0: inc(I);
#7: begin
inc(I);
Windows.Beep(800, 50);
Str := Str + '^';
end;
#10:
begin
inc(I);
AStrings.Add(Str);
Str := '';
end; {end #10}
#13:
begin
inc(I);
if (I < Bread) and (Buffer^[I] = #10) then
inc(I);
AStrings.Add(Str);
Str := '';
end; {end #13}
else
begin
Str := Str + Buffer^[I];
inc(I);
end; {end else}
end; {end case}
end; {end while}
Last := Str;
end; {end if}
Sleep(1);
Application.ProcessMessages;
until (ExitCode_ <> STILL_ACTIVE);
if Last <> '' then
AStrings.Add(Last);
finally
FreeMem(Buffer);
end; {end try/finally}
CloseHandle(PI.hThread);
CloseHandle(PI.hProcess);
CloseHandle(NewStdIn);
CloseHandle(NewStdOut);
CloseHandle(ReadStdOut);
CloseHandle(WriteStdIn);
end; {end procedure}

Answer 6

Here is a PHP specific solution, the project allows PHP to obtain and interact dynamically with a real cmd terminal. Get it here: https://github.com/merlinthemagic/MTS
After downloading you would simply use the following code:
//if you prefer Powershell, replace 'cmd' with 'powershell'
$shellObj = \MTS\Factories::getDevices()->getLocalHost()->getShell('cmd');
$strCmd1 = 'some_app.exe -param "test"';
$return1 = $shellObj->exeCmd($strCmd1);
The return will give you the command return OR error from cmd, just as if you sat at the console.
Furthermore, you can issue any command you like against the $shellObj, the environment is maintained throughout the life of the PHP script. So instead of bundling commands in a script file, just issue them one by one using the exeCmd() method, that way you can also handle the return and any exceptions.